This PPT deals with the effect of confinement/ encapsulation of different molecules inside fullerenes such as C16, C20, C60, C70 etc. Targeted drug delivery has also been extensively discussed. This is a group PPT done by Jyoti Devi, Vikas Katoch, Zeeshan Nazir and Aryaveer Singh. Some primary data has Also been collected by the publishers to find out the threshold fullerene for encapsulation of different di-atomic molecules inside fullerenes of different size.
The document reports on the crystal structure of a compound obtained unexpectedly from the recrystallization of (1R,2R)-1,2-diphenyl-1,2-propanediol. During recrystallization, the diol underwent a non-acid catalyzed pinacol rearrangement followed by acetal formation with another diol molecule. The resulting compound, 2α-(1,1-diphenylethyl)-4-methyl-4α,5α-diphenyl-1,3-dioxolane, was analyzed via X-ray crystallography. The dioxolane ring adopts a twisted conformation and molecules in the crystal lattice are linked by C-H
The document summarizes four new heterometallic molecular aggregates containing cobalt and lanthanide metals. Compounds 1 and 2 have the formula [(CoII)3(CoIII)2Ln3(μ3-OH)5(O2CtBu)12(L)2]·2H2O and feature distorted cubane cores, while compounds 3 and 4 have the formula [(CoIII)3Ln3(μ3-OH)4(O2CtBu)6(L)3](NO3)2·2CH3CN·2H2O and display hemicubane-like metallic cores. Magnetic studies show significant magnetic entropy changes for 1 and 3, and single molecule magnetic
Non-Stoichiometry & Solid Solution
The document discusses various types of point defects that can occur in non-stoichiometric compounds including Schottky defects, Frenkel defects, and anti-site defects. It provides examples of intrinsic point defects in metal-deficient, metal-excess, oxygen-deficient, and oxygen-excess metal oxides. Solid solutions are formed when one or more minor components dissolve uniformly within the crystal lattice of a major component. Types of solid solutions include interstitial, substitutional, ordered, and disordered solutions. Experimental techniques like X-ray diffraction and density measurements can be used to study properties of non-stoichiometric compounds and solid solutions.
Reduction of cu o and cu2o with h2 h embedding and kinetics effects in the ...Luciana Pirone
This document summarizes a study that used time-resolved X-ray diffraction, X-ray absorption fine structure spectroscopy, and density functional theory calculations to investigate the reduction of CuO and Cu2O with hydrogen gas. The main findings were:
1) CuO reduces directly to metallic copper without forming intermediate copper suboxides like Cu4O3 or Cu2O under normal hydrogen flow rates.
2) The reduction of CuO is easier than the reduction of Cu2O, with apparent activation energies of 14.5 kcal/mol and 27.4 kcal/mol, respectively.
3) During CuO reduction, the system can reach metastable states and react with hydrogen instead of
Key concepts of Geometrical Isomerism useful for the Undergraduate and Postgraduate students of Pharmacy , Chemistry and Post graduates of Pharmaceutical and Medicinal Chemistry
The document discusses the properties, synthesis, and applications of fullerenes, which are spherical or ellipsoidal molecules composed entirely of carbon. It describes the discovery and structure of C60 buckminsterfullerene and other fullerenes, as well as their physical and chemical properties. The document also outlines methods for synthesizing fullerenes using arc discharge and their potential applications in areas like catalysis, energy storage, and medicine.
This document discusses the structure of proteins at various levels:
1) Primary structure is the amino acid sequence of a polypeptide chain.
2) Secondary structure includes alpha helices and beta pleated sheets formed by hydrogen bonding between amino acids in the backbone.
3) Tertiary structure is the three-dimensional folding of the entire polypeptide chain, stabilized by interactions between amino acid side chains.
4) Quaternary structure refers to the association of multiple polypeptide subunits in a protein.
The document outlines techniques like X-ray crystallography and NMR that are used to determine protein structures at high resolution.
This document summarizes several theories and concepts related to stereochemistry in main group compounds, including:
1) VSEPR theory which describes the geometry of molecules based on electron pairs around the central atom. It explains linear, trigonal, tetrahedral, trigonal bipyramidal, and octahedral geometries.
2) Bent's rule which describes how atomic s-character concentrates in orbitals directed toward electropositive substituents.
3) Walsh diagrams which use molecular orbital energies to determine molecular geometry.
4) Berry pseudorotation and fluxionality concepts which explain rapid ligand exchange in molecules like PF5.
The document reports on the crystal structure of a compound obtained unexpectedly from the recrystallization of (1R,2R)-1,2-diphenyl-1,2-propanediol. During recrystallization, the diol underwent a non-acid catalyzed pinacol rearrangement followed by acetal formation with another diol molecule. The resulting compound, 2α-(1,1-diphenylethyl)-4-methyl-4α,5α-diphenyl-1,3-dioxolane, was analyzed via X-ray crystallography. The dioxolane ring adopts a twisted conformation and molecules in the crystal lattice are linked by C-H
The document summarizes four new heterometallic molecular aggregates containing cobalt and lanthanide metals. Compounds 1 and 2 have the formula [(CoII)3(CoIII)2Ln3(μ3-OH)5(O2CtBu)12(L)2]·2H2O and feature distorted cubane cores, while compounds 3 and 4 have the formula [(CoIII)3Ln3(μ3-OH)4(O2CtBu)6(L)3](NO3)2·2CH3CN·2H2O and display hemicubane-like metallic cores. Magnetic studies show significant magnetic entropy changes for 1 and 3, and single molecule magnetic
Non-Stoichiometry & Solid Solution
The document discusses various types of point defects that can occur in non-stoichiometric compounds including Schottky defects, Frenkel defects, and anti-site defects. It provides examples of intrinsic point defects in metal-deficient, metal-excess, oxygen-deficient, and oxygen-excess metal oxides. Solid solutions are formed when one or more minor components dissolve uniformly within the crystal lattice of a major component. Types of solid solutions include interstitial, substitutional, ordered, and disordered solutions. Experimental techniques like X-ray diffraction and density measurements can be used to study properties of non-stoichiometric compounds and solid solutions.
Reduction of cu o and cu2o with h2 h embedding and kinetics effects in the ...Luciana Pirone
This document summarizes a study that used time-resolved X-ray diffraction, X-ray absorption fine structure spectroscopy, and density functional theory calculations to investigate the reduction of CuO and Cu2O with hydrogen gas. The main findings were:
1) CuO reduces directly to metallic copper without forming intermediate copper suboxides like Cu4O3 or Cu2O under normal hydrogen flow rates.
2) The reduction of CuO is easier than the reduction of Cu2O, with apparent activation energies of 14.5 kcal/mol and 27.4 kcal/mol, respectively.
3) During CuO reduction, the system can reach metastable states and react with hydrogen instead of
Key concepts of Geometrical Isomerism useful for the Undergraduate and Postgraduate students of Pharmacy , Chemistry and Post graduates of Pharmaceutical and Medicinal Chemistry
The document discusses the properties, synthesis, and applications of fullerenes, which are spherical or ellipsoidal molecules composed entirely of carbon. It describes the discovery and structure of C60 buckminsterfullerene and other fullerenes, as well as their physical and chemical properties. The document also outlines methods for synthesizing fullerenes using arc discharge and their potential applications in areas like catalysis, energy storage, and medicine.
This document discusses the structure of proteins at various levels:
1) Primary structure is the amino acid sequence of a polypeptide chain.
2) Secondary structure includes alpha helices and beta pleated sheets formed by hydrogen bonding between amino acids in the backbone.
3) Tertiary structure is the three-dimensional folding of the entire polypeptide chain, stabilized by interactions between amino acid side chains.
4) Quaternary structure refers to the association of multiple polypeptide subunits in a protein.
The document outlines techniques like X-ray crystallography and NMR that are used to determine protein structures at high resolution.
This document summarizes several theories and concepts related to stereochemistry in main group compounds, including:
1) VSEPR theory which describes the geometry of molecules based on electron pairs around the central atom. It explains linear, trigonal, tetrahedral, trigonal bipyramidal, and octahedral geometries.
2) Bent's rule which describes how atomic s-character concentrates in orbitals directed toward electropositive substituents.
3) Walsh diagrams which use molecular orbital energies to determine molecular geometry.
4) Berry pseudorotation and fluxionality concepts which explain rapid ligand exchange in molecules like PF5.
A chemical bond is a lasting attraction between atoms that enables the formation of chemical compounds. The bond may result from the electrostatic force of attraction between atoms with opposite charges, or through the sharing of electrons as in the covalent bonds.
This document provides an outline for lessons on the topics of energetics and thermochemistry. It includes lessons on lattice enthalpy determination using Born-Haber cycles and enthalpies of solution. It also covers entropy, Gibbs free energy, and calculating changes in these properties for chemical reactions. Sample practice problems and review questions are provided to help teach these concepts and allow students to check their understanding.
British chemist Harry Kroto studied molecules with 60 carbon atoms found near red giant stars. He collaborated with Richard Smalley and Robert Curl to recreate C60 molecules in the lab using laser vaporization of graphite. They determined the structure was a combination of hexagonal and pentagonal carbon rings forming a spherical buckyball shape. Independently, Tony Haymet predicted a similar stable molecule. The discovery led to new fullerenes being synthesized and applications being found, including using exohedral and endohedral fullerenes for hydrogen storage and drug delivery.
Free radicals are atoms, molecules, or ions with unpaired electrons that make them highly reactive. They are formed through processes like homolysis and oxidation-reduction reactions. Free radical stability is determined by factors like conjugation, hybridization, and hyperconjugation which disperse and stabilize the unpaired electron. Common examples of stable radicals include molecular oxygen and organic radicals within conjugated systems.
This document discusses the stability and conformations of cyclohexane. It begins by explaining that molecules can exist in different three-dimensional shapes called conformations that are in equilibrium. It then describes the main conformations of cyclohexane: chair, boat, twist/skew boat, and half chair. The chair conformation is the most stable due to having the lowest strain from factors like bond distortion, charge repulsion, bond opposition, and steric effects. The conformations decrease in stability in the order of chair > twist boat > boat > half chair. The document defines axial and equatorial positions in the chair conformation and describes the different types of hydrogen atoms in the boat conformation. It concludes by noting that internal
This document discusses the stability and conformations of cyclohexane. It begins by explaining that molecules can exist in different three-dimensional shapes called conformations that are in equilibrium. It then describes the main conformations of cyclohexane: chair, boat, twist/skew boat, and half chair. The chair conformation is the most stable due to having the lowest strain from factors like bond distortion, charge repulsion, bond opposition, and steric effects. The conformations decrease in stability in the order of chair > twist boat > boat > half chair. The document defines axial and equatorial positions in the chair conformation and describes the different types of hydrogen atoms in the boat conformation. It concludes by noting that internal
Computationally Driven Characterization of Magnetism, Adsorption, and Reactiv...Joshua Borycz
Metal organic frameworks (MOFs) are a class of nanoporous materials that are com- posed of metal-containing nodes connected by organic linkers. The study of MOFs has grown in importance due to the wide range of possible node and linker combinations, which allow tailoring towards specific applications. This work demonstrates that the- ory can complement experiment in a way that advances the chemical understanding of MOFs. This thesis contains the results of several investigations on three different areas of MOF research: 1) magnetism, 2) CO2 adsorption, and 3) catalysis.
Isotopes are two atoms of the same element that have the same number of protons but different numbers of neutrons. Isotopes are specified by the mass number.
Cyclohexane exists in stable chair and boat conformations. The chair conformation is more stable due to minimal angle and torsional strain. Substituents on cyclohexane can exist in axial or equatorial positions, with the equatorial position generally being more stable due to less 1,3-diaxial interactions. Disubstituted cyclohexanes can exist as cis or trans isomers, with the trans isomer being more stable for 1,2-disubstituted cyclohexanes due to less van der Waals strain.
This document provides information about chemical bonding over 14 lectures. It discusses various theories of bonding including Kossel-Lewis concept, VSEPR theory, valence bond theory and molecular orbital theory. It describes different types of bonds such as ionic, covalent and dative bonds. It also discusses topics like bond polarity, dipole moment, Fajan's rule, VSEPR theory, bond properties and factors affecting stability of molecules.
Cyclic conformation and nucleic acid sugar puckeringDaniel Morton
Cyclic systems are ubiquitous, in nature and synthetic chemistry. Establishing an understanding of the shape preferences (e.g., strain and energetics) regarding representative cyclic models is a powerful tool in conformational analysis. The expanded review of fundamental cycloalkanes can further assist in preferential conformational analysis of associated derivatives.
Contributed by: Roland Jones, Dane Brankle, and Peter Stevenson, University of Utah, 2015
A first principles study into the properties and activities of rare-earth and...Hnakey Lora
This document discusses density functional theory calculations to study the properties and activities of rare-earth and transition metal materials for environmental catalysis and medical applications. It examines the mechanisms of ceria-based oxygen storage materials, NOx removal, and low-temperature catalysis. Specific topics covered include oxygen vacancy formation in ceria, the roles of cerium and zirconium in oxygen storage capacity, NO oxidation on precious metals and their oxides, and low-temperature CO and ethylene combustion using gold films, cobalt oxide, and manganese oxide catalysts.
Carbon corrosion and platinum nanoparticles ripening under open circuit poten...LandimarMendesDuarte
This document discusses a study examining the degradation of platinum nanoparticles supported on Vulcan XC72 carbon under open circuit potential conditions over 3.5 years. Characterization techniques showed that the amorphous domains of the carbon support were preferentially oxidized into CO2 during aging, while the organized domains were more slowly oxidized, producing mostly oxygen-containing surface groups and minor CO2. Over time, platinum nanoparticle aggregation and detachment from the carbon support increased due to platinum-catalyzed carbon corrosion.
This document covers bonding theories including molecular orbital theory, valence bond theory, and VSEPR theory. It begins with examples of applying concepts like electronegativity, oxidation states, and formal charge to molecules like O3, H2O2, CO, and transition metal compounds. It then discusses valence shell electron pair repulsion theory and how to predict molecular structures. Next, it introduces valence bond theory and hybridization. Molecular orbital theory is covered last, including forming ligand group orbitals, constructing molecular orbitals, and discussing applications to coordination compounds and aromatic ligands.
Perovskite Solar Cells
a short general overview presentation
hadi maghsoudi
device structure
crystal structure
preparation synthesis method
review papers
This study examines the crystal structure of a cytochrome c peroxidase mutant where the distal catalytic histidine 52 is converted to tyrosine. The crystal structure reveals an unprecedented covalent bond between the indole nitrogen of tryptophan 51 and the phenyl group of tyrosine 52. The authors hypothesize that this novel cross-link results from peroxide activation by the heme iron, followed by oxidation of tryptophan 51 and tyrosine 52. Testing of this hypothesis by incorporating a redox-inactive zinc-protoporphyrin, which showed the absence of the cross-link, supports that the cross-link is a peroxide-dependent process mediated by the heme iron. Additional experiments treating heme-containing
This course provides an in-depth understanding of three-dimensional macromolecular structure and the relationship between the conformation of proteins and nucleic acids and their biological functions. Students will learn to visualize and analyze macromolecular structures using molecular graphics software and assess the structural basis of biological activity. The course covers topics related to multi-molecular assemblies, catalytic machines, and membrane proteins. Students will be assessed through a final exam and computer graphics exercises completed in a lab notebook.
The document discusses chemical bonding and molecular structure. It begins by introducing different types of chemical bonds including ionic and covalent bonds. It then discusses how valence electrons are distributed in molecules as either bond pairs or lone pairs according to the octet rule. Examples of drawing Lewis structures for different molecules like NH3, CO2, and SO32- are provided. The document also discusses exceptions to the octet rule and concepts like formal charge, resonance structures, and bond order. Finally, it introduces VSEPR theory for predicting molecular geometry and discusses how bond properties like length and energy depend on factors like bond order.
This study examines dissociation pathways in the dication of the amino acid cysteine after site-selective core ionization of the O 1s, N 1s, C 1s, and S 2p orbitals. A photoelectron-ion-ion coincidence experiment was performed. Several dissociation channels were identified, some showing strong site-selective dependence attributed to a combination of nuclear motion in the core-ionized state and Auger processes populating different electronic states in the dication. Fragmentation patterns were analyzed at each core ionization level to determine dissociation pathways and kinetic energy release partitioning between fragments through regression slope analysis.
Hydro-Thermal Liquefaction Of Lignocellulosic biomass to produce Bio-Crude oilZeeshan Nazir
Hydrothermal liquefaction is a promising method to produce bio-crude oil from lignocellulosic biomass as a renewable alternative to petroleum. It involves decomposing biomass at high pressure and temperatures between 200-350°C to produce bio-crude with a higher energy density than methods like pyrolysis and gasification. Some key advantages over other methods include low operating costs, applicability to many biomass feedstocks, lower capital requirements, and producings a safer end product. The goal of this research is to produce 3 million tonnes per year of bio-crude using hydrothermal liquefaction of abundant biomass resources to help address future energy demands.
This document discusses supercritical fluid extraction as an alternative to conventional extraction methods. Supercritical fluids exist above the critical point where distinct liquid and gas phases do not exist. They have good extractive capacity and are safer than traditional organic solvents. Supercritical fluid extraction is faster, more efficient, selective, and environmentally friendly compared to conventional methods like maceration, percolation, and reflux extraction which are time-consuming, use toxic solvents, require high energy, and have low yields. It provides a sustainable solution for separating flavors, fragrances, caffeine, nicotine, pharmaceuticals, aromas, polymers and more from materials.
A chemical bond is a lasting attraction between atoms that enables the formation of chemical compounds. The bond may result from the electrostatic force of attraction between atoms with opposite charges, or through the sharing of electrons as in the covalent bonds.
This document provides an outline for lessons on the topics of energetics and thermochemistry. It includes lessons on lattice enthalpy determination using Born-Haber cycles and enthalpies of solution. It also covers entropy, Gibbs free energy, and calculating changes in these properties for chemical reactions. Sample practice problems and review questions are provided to help teach these concepts and allow students to check their understanding.
British chemist Harry Kroto studied molecules with 60 carbon atoms found near red giant stars. He collaborated with Richard Smalley and Robert Curl to recreate C60 molecules in the lab using laser vaporization of graphite. They determined the structure was a combination of hexagonal and pentagonal carbon rings forming a spherical buckyball shape. Independently, Tony Haymet predicted a similar stable molecule. The discovery led to new fullerenes being synthesized and applications being found, including using exohedral and endohedral fullerenes for hydrogen storage and drug delivery.
Free radicals are atoms, molecules, or ions with unpaired electrons that make them highly reactive. They are formed through processes like homolysis and oxidation-reduction reactions. Free radical stability is determined by factors like conjugation, hybridization, and hyperconjugation which disperse and stabilize the unpaired electron. Common examples of stable radicals include molecular oxygen and organic radicals within conjugated systems.
This document discusses the stability and conformations of cyclohexane. It begins by explaining that molecules can exist in different three-dimensional shapes called conformations that are in equilibrium. It then describes the main conformations of cyclohexane: chair, boat, twist/skew boat, and half chair. The chair conformation is the most stable due to having the lowest strain from factors like bond distortion, charge repulsion, bond opposition, and steric effects. The conformations decrease in stability in the order of chair > twist boat > boat > half chair. The document defines axial and equatorial positions in the chair conformation and describes the different types of hydrogen atoms in the boat conformation. It concludes by noting that internal
This document discusses the stability and conformations of cyclohexane. It begins by explaining that molecules can exist in different three-dimensional shapes called conformations that are in equilibrium. It then describes the main conformations of cyclohexane: chair, boat, twist/skew boat, and half chair. The chair conformation is the most stable due to having the lowest strain from factors like bond distortion, charge repulsion, bond opposition, and steric effects. The conformations decrease in stability in the order of chair > twist boat > boat > half chair. The document defines axial and equatorial positions in the chair conformation and describes the different types of hydrogen atoms in the boat conformation. It concludes by noting that internal
Computationally Driven Characterization of Magnetism, Adsorption, and Reactiv...Joshua Borycz
Metal organic frameworks (MOFs) are a class of nanoporous materials that are com- posed of metal-containing nodes connected by organic linkers. The study of MOFs has grown in importance due to the wide range of possible node and linker combinations, which allow tailoring towards specific applications. This work demonstrates that the- ory can complement experiment in a way that advances the chemical understanding of MOFs. This thesis contains the results of several investigations on three different areas of MOF research: 1) magnetism, 2) CO2 adsorption, and 3) catalysis.
Isotopes are two atoms of the same element that have the same number of protons but different numbers of neutrons. Isotopes are specified by the mass number.
Cyclohexane exists in stable chair and boat conformations. The chair conformation is more stable due to minimal angle and torsional strain. Substituents on cyclohexane can exist in axial or equatorial positions, with the equatorial position generally being more stable due to less 1,3-diaxial interactions. Disubstituted cyclohexanes can exist as cis or trans isomers, with the trans isomer being more stable for 1,2-disubstituted cyclohexanes due to less van der Waals strain.
This document provides information about chemical bonding over 14 lectures. It discusses various theories of bonding including Kossel-Lewis concept, VSEPR theory, valence bond theory and molecular orbital theory. It describes different types of bonds such as ionic, covalent and dative bonds. It also discusses topics like bond polarity, dipole moment, Fajan's rule, VSEPR theory, bond properties and factors affecting stability of molecules.
Cyclic conformation and nucleic acid sugar puckeringDaniel Morton
Cyclic systems are ubiquitous, in nature and synthetic chemistry. Establishing an understanding of the shape preferences (e.g., strain and energetics) regarding representative cyclic models is a powerful tool in conformational analysis. The expanded review of fundamental cycloalkanes can further assist in preferential conformational analysis of associated derivatives.
Contributed by: Roland Jones, Dane Brankle, and Peter Stevenson, University of Utah, 2015
A first principles study into the properties and activities of rare-earth and...Hnakey Lora
This document discusses density functional theory calculations to study the properties and activities of rare-earth and transition metal materials for environmental catalysis and medical applications. It examines the mechanisms of ceria-based oxygen storage materials, NOx removal, and low-temperature catalysis. Specific topics covered include oxygen vacancy formation in ceria, the roles of cerium and zirconium in oxygen storage capacity, NO oxidation on precious metals and their oxides, and low-temperature CO and ethylene combustion using gold films, cobalt oxide, and manganese oxide catalysts.
Carbon corrosion and platinum nanoparticles ripening under open circuit poten...LandimarMendesDuarte
This document discusses a study examining the degradation of platinum nanoparticles supported on Vulcan XC72 carbon under open circuit potential conditions over 3.5 years. Characterization techniques showed that the amorphous domains of the carbon support were preferentially oxidized into CO2 during aging, while the organized domains were more slowly oxidized, producing mostly oxygen-containing surface groups and minor CO2. Over time, platinum nanoparticle aggregation and detachment from the carbon support increased due to platinum-catalyzed carbon corrosion.
This document covers bonding theories including molecular orbital theory, valence bond theory, and VSEPR theory. It begins with examples of applying concepts like electronegativity, oxidation states, and formal charge to molecules like O3, H2O2, CO, and transition metal compounds. It then discusses valence shell electron pair repulsion theory and how to predict molecular structures. Next, it introduces valence bond theory and hybridization. Molecular orbital theory is covered last, including forming ligand group orbitals, constructing molecular orbitals, and discussing applications to coordination compounds and aromatic ligands.
Perovskite Solar Cells
a short general overview presentation
hadi maghsoudi
device structure
crystal structure
preparation synthesis method
review papers
This study examines the crystal structure of a cytochrome c peroxidase mutant where the distal catalytic histidine 52 is converted to tyrosine. The crystal structure reveals an unprecedented covalent bond between the indole nitrogen of tryptophan 51 and the phenyl group of tyrosine 52. The authors hypothesize that this novel cross-link results from peroxide activation by the heme iron, followed by oxidation of tryptophan 51 and tyrosine 52. Testing of this hypothesis by incorporating a redox-inactive zinc-protoporphyrin, which showed the absence of the cross-link, supports that the cross-link is a peroxide-dependent process mediated by the heme iron. Additional experiments treating heme-containing
This course provides an in-depth understanding of three-dimensional macromolecular structure and the relationship between the conformation of proteins and nucleic acids and their biological functions. Students will learn to visualize and analyze macromolecular structures using molecular graphics software and assess the structural basis of biological activity. The course covers topics related to multi-molecular assemblies, catalytic machines, and membrane proteins. Students will be assessed through a final exam and computer graphics exercises completed in a lab notebook.
The document discusses chemical bonding and molecular structure. It begins by introducing different types of chemical bonds including ionic and covalent bonds. It then discusses how valence electrons are distributed in molecules as either bond pairs or lone pairs according to the octet rule. Examples of drawing Lewis structures for different molecules like NH3, CO2, and SO32- are provided. The document also discusses exceptions to the octet rule and concepts like formal charge, resonance structures, and bond order. Finally, it introduces VSEPR theory for predicting molecular geometry and discusses how bond properties like length and energy depend on factors like bond order.
This study examines dissociation pathways in the dication of the amino acid cysteine after site-selective core ionization of the O 1s, N 1s, C 1s, and S 2p orbitals. A photoelectron-ion-ion coincidence experiment was performed. Several dissociation channels were identified, some showing strong site-selective dependence attributed to a combination of nuclear motion in the core-ionized state and Auger processes populating different electronic states in the dication. Fragmentation patterns were analyzed at each core ionization level to determine dissociation pathways and kinetic energy release partitioning between fragments through regression slope analysis.
Similar to Fullerenes-An explorative study.pptx (20)
Hydro-Thermal Liquefaction Of Lignocellulosic biomass to produce Bio-Crude oilZeeshan Nazir
Hydrothermal liquefaction is a promising method to produce bio-crude oil from lignocellulosic biomass as a renewable alternative to petroleum. It involves decomposing biomass at high pressure and temperatures between 200-350°C to produce bio-crude with a higher energy density than methods like pyrolysis and gasification. Some key advantages over other methods include low operating costs, applicability to many biomass feedstocks, lower capital requirements, and producings a safer end product. The goal of this research is to produce 3 million tonnes per year of bio-crude using hydrothermal liquefaction of abundant biomass resources to help address future energy demands.
This document discusses supercritical fluid extraction as an alternative to conventional extraction methods. Supercritical fluids exist above the critical point where distinct liquid and gas phases do not exist. They have good extractive capacity and are safer than traditional organic solvents. Supercritical fluid extraction is faster, more efficient, selective, and environmentally friendly compared to conventional methods like maceration, percolation, and reflux extraction which are time-consuming, use toxic solvents, require high energy, and have low yields. It provides a sustainable solution for separating flavors, fragrances, caffeine, nicotine, pharmaceuticals, aromas, polymers and more from materials.
Miller indices are a set of three numbers used to specify lattice planes in crystal structures. To calculate the Miller indices of a plane, the intercepts of the plane with the X, Y, and Z axes are taken and the reciprocal is calculated. For example, a plane with intercepts of X=∞, Y=1, Z=∞ would have Miller indices of (010). If a plane passes through the origin, the origin must be shifted to the nearest lattice point to calculate the intercepts.
This document discusses fullerenes and carbon nanotubes. It begins by introducing fullerenes, known as buckyballs, which are spherical carbon molecules. It describes their structure and applications, including use in semiconductors, batteries, and medicine. The document then discusses carbon nanotubes, which are cylindrical structures made of carbon atoms. It outlines their structure and various applications in electronics due to properties like strength, size, energy efficiency, and durability. In electronics, carbon nanotubes can protect against hardware attacks, enable smaller devices, and reduce power consumption compared to traditional RAM.
Effects of confinement on amino acids inside fullerene cages.pptxZeeshan Nazir
This document summarizes research on glycine molecules confined inside fullerene cages. The researchers used density functional theory to optimize molecular geometries and electronic structures of glycine in different confinement environments. They found that confinement led to variations in bond lengths and angles compared to isolated glycine. Specifically, one conformer of glycine was observed to change into a zwitterion structure inside one cage due to proton transfer. Overall, confinement had notable impacts on the molecular structure of glycine.
This document discusses heterogeneous catalysis. It notes that 65% of world GDP and 90% of chemicals by volume are influenced or assisted by solid catalysis. It also notes that 144 million tons of ammonia are produced annually, with 130 billion kilograms produced in 2018 alone. It defines catalysis as the process of altering a chemical reaction rate by adding a catalyst and defines the differences between homogeneous, heterogeneous, and bio-catalysis. Heterogeneous catalysis involves a catalyst in a different phase than the reactants or products. The Haber-Bosch process and platinum catalyst are discussed as examples. Surface reactions like Langmuir-Hinshelwood and Eley-Rideal mechanisms are also summarized. The document
Epoxide, nomenclature, synthesis, ring opening, regio-selectivityZeeshan Nazir
This document summarizes a presentation on epoxides given by Zeeshan Nazir to the Department of Chemistry and Chemical Sciences at Central University of Jammu. It covers the topics of nomenclature, synthesis, and ring opening of epoxides. Epoxides are cyclic ethers with a three-membered ring that are more reactive than typical ethers due to ring strain. They are commonly synthesized through epoxidation of alkenes using organic peroxy acids or via intramolecular Williamson ether synthesis of halohydrins. Epoxide rings can be opened through acid-catalyzed or base-catalyzed nucleophilic attack, with bases preferentially attacking the less
Ion-exchange chromatography separates molecules like proteins and nucleic acids based on their surface charge. It uses a stationary phase resin with charged groups and a mobile buffer phase. Proteins bind to the resin based on their net charge at a given pH. Elution can occur by changing the salt concentration or pH of the mobile phase. This document discusses the principles and procedures of ion-exchange chromatography, including how changing pH allows separation of proteins based on their individual isoelectric points.
ANAMOLOUS SECONDARY GROWTH IN DICOT ROOTS.pptxRASHMI M G
Abnormal or anomalous secondary growth in plants. It defines secondary growth as an increase in plant girth due to vascular cambium or cork cambium. Anomalous secondary growth does not follow the normal pattern of a single vascular cambium producing xylem internally and phloem externally.
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...Sérgio Sacani
Context. With a mass exceeding several 104 M⊙ and a rich and dense population of massive stars, supermassive young star clusters
represent the most massive star-forming environment that is dominated by the feedback from massive stars and gravitational interactions
among stars.
Aims. In this paper we present the Extended Westerlund 1 and 2 Open Clusters Survey (EWOCS) project, which aims to investigate
the influence of the starburst environment on the formation of stars and planets, and on the evolution of both low and high mass stars.
The primary targets of this project are Westerlund 1 and 2, the closest supermassive star clusters to the Sun.
Methods. The project is based primarily on recent observations conducted with the Chandra and JWST observatories. Specifically,
the Chandra survey of Westerlund 1 consists of 36 new ACIS-I observations, nearly co-pointed, for a total exposure time of 1 Msec.
Additionally, we included 8 archival Chandra/ACIS-S observations. This paper presents the resulting catalog of X-ray sources within
and around Westerlund 1. Sources were detected by combining various existing methods, and photon extraction and source validation
were carried out using the ACIS-Extract software.
Results. The EWOCS X-ray catalog comprises 5963 validated sources out of the 9420 initially provided to ACIS-Extract, reaching a
photon flux threshold of approximately 2 × 10−8 photons cm−2
s
−1
. The X-ray sources exhibit a highly concentrated spatial distribution,
with 1075 sources located within the central 1 arcmin. We have successfully detected X-ray emissions from 126 out of the 166 known
massive stars of the cluster, and we have collected over 71 000 photons from the magnetar CXO J164710.20-455217.
What is greenhouse gasses and how many gasses are there to affect the Earth.moosaasad1975
What are greenhouse gasses how they affect the earth and its environment what is the future of the environment and earth how the weather and the climate effects.
Travis Hills' Endeavors in Minnesota: Fostering Environmental and Economic Pr...Travis Hills MN
Travis Hills of Minnesota developed a method to convert waste into high-value dry fertilizer, significantly enriching soil quality. By providing farmers with a valuable resource derived from waste, Travis Hills helps enhance farm profitability while promoting environmental stewardship. Travis Hills' sustainable practices lead to cost savings and increased revenue for farmers by improving resource efficiency and reducing waste.
When I was asked to give a companion lecture in support of ‘The Philosophy of Science’ (https://shorturl.at/4pUXz) I decided not to walk through the detail of the many methodologies in order of use. Instead, I chose to employ a long standing, and ongoing, scientific development as an exemplar. And so, I chose the ever evolving story of Thermodynamics as a scientific investigation at its best.
Conducted over a period of >200 years, Thermodynamics R&D, and application, benefitted from the highest levels of professionalism, collaboration, and technical thoroughness. New layers of application, methodology, and practice were made possible by the progressive advance of technology. In turn, this has seen measurement and modelling accuracy continually improved at a micro and macro level.
Perhaps most importantly, Thermodynamics rapidly became a primary tool in the advance of applied science/engineering/technology, spanning micro-tech, to aerospace and cosmology. I can think of no better a story to illustrate the breadth of scientific methodologies and applications at their best.
ESR spectroscopy in liquid food and beverages.pptxPRIYANKA PATEL
With increasing population, people need to rely on packaged food stuffs. Packaging of food materials requires the preservation of food. There are various methods for the treatment of food to preserve them and irradiation treatment of food is one of them. It is the most common and the most harmless method for the food preservation as it does not alter the necessary micronutrients of food materials. Although irradiated food doesn’t cause any harm to the human health but still the quality assessment of food is required to provide consumers with necessary information about the food. ESR spectroscopy is the most sophisticated way to investigate the quality of the food and the free radicals induced during the processing of the food. ESR spin trapping technique is useful for the detection of highly unstable radicals in the food. The antioxidant capability of liquid food and beverages in mainly performed by spin trapping technique.
Phenomics assisted breeding in crop improvementIshaGoswami9
As the population is increasing and will reach about 9 billion upto 2050. Also due to climate change, it is difficult to meet the food requirement of such a large population. Facing the challenges presented by resource shortages, climate
change, and increasing global population, crop yield and quality need to be improved in a sustainable way over the coming decades. Genetic improvement by breeding is the best way to increase crop productivity. With the rapid progression of functional
genomics, an increasing number of crop genomes have been sequenced and dozens of genes influencing key agronomic traits have been identified. However, current genome sequence information has not been adequately exploited for understanding
the complex characteristics of multiple gene, owing to a lack of crop phenotypic data. Efficient, automatic, and accurate technologies and platforms that can capture phenotypic data that can
be linked to genomics information for crop improvement at all growth stages have become as important as genotyping. Thus,
high-throughput phenotyping has become the major bottleneck restricting crop breeding. Plant phenomics has been defined as the high-throughput, accurate acquisition and analysis of multi-dimensional phenotypes
during crop growing stages at the organism level, including the cell, tissue, organ, individual plant, plot, and field levels. With the rapid development of novel sensors, imaging technology,
and analysis methods, numerous infrastructure platforms have been developed for phenotyping.
hematic appreciation test is a psychological assessment tool used to measure an individual's appreciation and understanding of specific themes or topics. This test helps to evaluate an individual's ability to connect different ideas and concepts within a given theme, as well as their overall comprehension and interpretation skills. The results of the test can provide valuable insights into an individual's cognitive abilities, creativity, and critical thinking skills
The ability to recreate computational results with minimal effort and actionable metrics provides a solid foundation for scientific research and software development. When people can replicate an analysis at the touch of a button using open-source software, open data, and methods to assess and compare proposals, it significantly eases verification of results, engagement with a diverse range of contributors, and progress. However, we have yet to fully achieve this; there are still many sociotechnical frictions.
Inspired by David Donoho's vision, this talk aims to revisit the three crucial pillars of frictionless reproducibility (data sharing, code sharing, and competitive challenges) with the perspective of deep software variability.
Our observation is that multiple layers — hardware, operating systems, third-party libraries, software versions, input data, compile-time options, and parameters — are subject to variability that exacerbates frictions but is also essential for achieving robust, generalizable results and fostering innovation. I will first review the literature, providing evidence of how the complex variability interactions across these layers affect qualitative and quantitative software properties, thereby complicating the reproduction and replication of scientific studies in various fields.
I will then present some software engineering and AI techniques that can support the strategic exploration of variability spaces. These include the use of abstractions and models (e.g., feature models), sampling strategies (e.g., uniform, random), cost-effective measurements (e.g., incremental build of software configurations), and dimensionality reduction methods (e.g., transfer learning, feature selection, software debloating).
I will finally argue that deep variability is both the problem and solution of frictionless reproducibility, calling the software science community to develop new methods and tools to manage variability and foster reproducibility in software systems.
Exposé invité Journées Nationales du GDR GPL 2024
The debris of the ‘last major merger’ is dynamically youngSérgio Sacani
The Milky Way’s (MW) inner stellar halo contains an [Fe/H]-rich component with highly eccentric orbits, often referred to as the
‘last major merger.’ Hypotheses for the origin of this component include Gaia-Sausage/Enceladus (GSE), where the progenitor
collided with the MW proto-disc 8–11 Gyr ago, and the Virgo Radial Merger (VRM), where the progenitor collided with the
MW disc within the last 3 Gyr. These two scenarios make different predictions about observable structure in local phase space,
because the morphology of debris depends on how long it has had to phase mix. The recently identified phase-space folds in Gaia
DR3 have positive caustic velocities, making them fundamentally different than the phase-mixed chevrons found in simulations
at late times. Roughly 20 per cent of the stars in the prograde local stellar halo are associated with the observed caustics. Based
on a simple phase-mixing model, the observed number of caustics are consistent with a merger that occurred 1–2 Gyr ago.
We also compare the observed phase-space distribution to FIRE-2 Latte simulations of GSE-like mergers, using a quantitative
measurement of phase mixing (2D causticality). The observed local phase-space distribution best matches the simulated data
1–2 Gyr after collision, and certainly not later than 3 Gyr. This is further evidence that the progenitor of the ‘last major merger’
did not collide with the MW proto-disc at early times, as is thought for the GSE, but instead collided with the MW disc within
the last few Gyr, consistent with the body of work surrounding the VRM.
This presentation explores a brief idea about the structural and functional attributes of nucleotides, the structure and function of genetic materials along with the impact of UV rays and pH upon them.
1. ENDOHEDRAL FULLERENES
Date: 04 July, 2022 Central
University
of Jammu
Department of Chemistry
and Chemical Sciences.
Aryaveer, Jyoti, Vikas and Zeeshan
2. Table of Contents
• Introduction
• Encapsulation of Small molecules
• Encapsulation of Metals
• Encapsulation of Biological molecules
• Silicon Fullerenes
• Computational Analysis
• References
2
4. Fullerenes
• Allotropes of carbon.
• The first ever fullerene was discovered by Sir Harold W. Kroto.
• Follows IPR (Isolated Pentagon Rule).
• Most popular – C60.
• sp2hybridized.
Animation reference: commons.m.Wikipedia.org 4
5. Endohedral fullerenes
Insertion or incarceration of an atom or
molecule inside a cage of carbon atoms
(fullerenes) resulting in the formation of
endohedral or encapsulated fullerenes.
5
6. Why is it done?
• Isolate different atoms or molecules
• Molecular electronics
• Nano-technology
• Targeted drug delivery
6
7. How is it done?
• Opening of Cage
• Placement of atom or molecule
• Closing of cage
Molecular
Surgery Method
7
8. Encapsulation of small molecules
Figure reference: Zhang, R.; et al. Synthesis of a distinct water dimer inside fullerene C70. Nature Chemistry. 2016, 8, 435-441.
8
Encapsulation depends majorly upon the size of the molecule and fullerene.
9. Encapsulation of
H2 molecule in C60
fullerene
Molecular
surgery method
No effect on C60 cage
due to encapsulation of
H2
High
temperature is
avoided
67% yield
produced
Reversing by
HPLC
Scheme reference: Komatsu, K.; et al. Encapsulation of molecular hydrogen in fullerene C60 by organic synthesis. Science. 2007, 307, 238-240.
9
12. Metal-metal bonds in EMFs
• In EMFs, the internal metal atoms always donate electrons to the fullerene cage. [1]
• Produces unique structures and fascinating electronic properties of EMFs.
• The encapsulated metal atoms can move around in fullerene cage at room temperature.
• Application in electronics, magnetism, and photovoltaics.
12
13. Encapsulation of 2 Lu atoms inside C76
• The two lutetium atoms in dimetallofullerene Lu2@C76 prefer to bind together to form
an unprecedented single metal–metal bond, in a formal valence state of [Lu2]4+@C76
4-
• HOMO-LUMO gap in [Lu2]4+@C76 (1.49eV) is close to the gap (1.71eV) calculated
at tetra-anion state. [2]
• [Lu2]4+@C76
4- [Lu2]6+@C76
6-
Correct Incorrect
13
14. Hopping of Lu2 dimer
• It has been shown that the Lu atoms can hop rapidly between six equivalent
configurations in the fullerene cage at room temperature, giving rise to a trajectory as a
tetrahedron in C76 (Td). [3]
14
Six equivalent configurations of Lu2 dimer as a tetrahedron in C76
15. Nature of bonding and Bond length
• Two-electron two-centre bond
• Back donation of negative charge from carbon cage to metal atomic orbital.
• The interaction between the encapsulated Lu2
4+ dimer and the C76
4- cage includes both
ionic and covalent ones.
• The predicted Lu-Lu bond length is 3.42 A, much shorter than the single Lu-Lu bond
length (3.82 A) in the crystals.
15
16. Stability
• Bonding energy : Strain energy (destabilizing term) and Interaction energy (stabilizing
term).
• Strain energy for Lu2 is 12.8 kcalmol-1 .
Strain energy for C76 is 52.0 kcalmol-1 .
• The interaction energy is -168.7 kcalmol-1 due to electron transfer and orbital
overlaps.
• To summarize, the bonding energy is 103.9 kcalmol-1, which is large enough to keep
Lu2@C76 (Td) stable.
16
22. Unusual behaviour of ‘C’ conformer
22
Dramatic decrease in C-O bond length (1.33 Å to 1.21 Å)
Unusual increase in OCO bond angle (123.60 to 128.260 )
Reason being: glycine (C) changes to zwitter-ion upon confinement
By proton transfer from hydroxyl towards amino group
Changing hybridisation of O-atom to SP2 from SP3
Unusual Increase in C=O bond length (1.19 Å to 1.21 Å)
23. Exohedral vs Isolated/ Relaxed
23
Aisolated AOS Bisolated BOS Cisolated COS Disolated DOS Eisolated EOS
rN-H 1.01 1.02 1.01 1.02 1.01 1.02 1.09 1.02 1.01 1.03
rC-H 1.09 1.09 1.09 1.11 1.09 1.10 0.97 1.09 1.01 1.1
rO-H 0.98 0.99 0.97 - 0.98 0.98 1.45 1.04 1.10 1.01
rC-N 1.46 1.48 1.45 1.46 1.46 1.47 1.51 1.49 0.96 1.49
rC-C 1.53 1.54 1.52 1.52 1.53 1.54 1.20 1.56 1.44 1.54
rC=O 1.19 1.21 1.20 1.21 1.19 1.44 1.34 1.22 1.53 1.22
rC-O 1.33 - 1.35 1.35 1.33 1.38 1.01 1.35 1.19 1.36
OS: Reported structure of glycine in other systems
AOS reference [5] BOS reference [5] EOS reference [7]
DOS reference
[6]
COS reference [5]
24. HB in confined AAs
24
HB possess a strong covalent character.
Serine
Glycine Alanine
While Conventional HB is of electrostatic nature.
Image references: Shahamirian, M,; Azami S.M [8]
28. Effect on Tumor
28
Untreated DTX C60-PEI/DTX C60-PEI-FA/DTX
After sacrificing the mice at the end of treatment of 14 days [6].
Image Courtesy: Shi, J. et al [6]
30. 1. C60-OH-APA-DTX. Prepared by N. Thotakura et al. [10]
30
5.8 times increase in the bioavailability of the drug.
Better cell apoptosis.
Enhanced cellular uptake.
31. 31
2. Folic Acid γ -Cyclodextrin C60. Liu et al. [11]
High aqueous solubility and pH-sensitive drug release.
Higher accumulation in tumor cells
Potent therapeutic effect and low toxicity of FA-γCD-C60
34. SILICON FULLERENE
: Stable
: Unstable
1. Encapsulation of Metals
2. Adsorption of Hydrogen On Silicon Cages
Methods to reduce
in-stability:
34
35. 1. Encapsulation of metal inside Silicon fullerene
In 2001, Kumar and Kawazoe optimized Dodecahedral Si20 Fullerene, by encapsulation of Zr atom. [12]
Fig.Shrinkage of the Si20
cage: (a) Dodecahedral Zr-encapsulated Zr@Si20
(b)–(e)optimized structures of Zr@Si20
, Zr@Si19
, Zr@Si17
, and Zr@Si16
, respectively (f) The polyhedral structure of Ti@Si16.(1)
35
37. Examples
Fig. (a)Metal encapsulated fullerene cages of Ni@Si12
,W@Si14
, and Zr@Si16
(b) The optimized structures of (from left to right) Th@Si20
fullerene, Be@Si8
cubic, W@Si12
hexagonal prism, and chair shaped Be@Si12
, respectively (1)
37
38. 2. Adsorption of Hydrogen On Silicon Cages
Fig. Optimized structures of (a) Si16ZrH8 (b) Si16ZrH8 (c) Si16ZrH16, (d) Si12H12, (e) Si16H16, and (f)
Si20H20
(1)
38
39. Effect on Silicon Fullerenes:
• Very strong bonding between M and Si atoms.
• H adsorption enhances sp3 between Silicon atoms.
• The High HOMO-LUMO gap.
OVERALL ENERGY
DECREASED AND
STABILITY
INCREASED
39
40. What we have done
Table reference://nanotube.msu.edu/fullerene/
Different fullerenes on the basis of size.
40
41. 1.Threshold fullerene for H2(C20).
Equilibrium structure of H2@C20 computed at B3LYP/6-31g(d,p) level of theory.
2.Threshold fullerene for N
2
(C
28
).
Equilibrium structure of N2@C28using B3LYP/6-31g(d,p) level of theory.
41
42. 3. Threshold fullerene for O2(C28).
Equilibrium structure O2@C28 optimized using B3LYP/6-31g(d) level of theory
4. Threshold fullerene for F2(C32).
Equilibrium structure of F2@C32 using B3LYP/6-31g(d,p) level of theory.
43. References
1. Kobayashi, K. et al.,Endohedral dimetallofullerenes Sc2@C84 and La2@C80. Are the metal atoms still inside the fullerence
cages?,Chemical Physics Letter. 1996, 246, 502-506.
2. Takeshi A; et al. 13C and 139La NMR Studies of La2@C80: First Evidence for Circular Motion of Metal Atoms in Endohedral
Dimetallofullerenes. Communications. 2008, 36, 1643–1645.
3. Yamada, M. et al. Synthesis and characterization of the D5h isomer of the endohedral dimetallofullerene Ce2@C80: two-
dimensional circulation of encapsulated metal atoms inside a fullerene cage. Chemistry Europe. 2009, 21, 9486-93.
4. Shahamirian, M.; Azami, S.M.; Encapsulation of glycine inside C60 fullerene: Impact of confinement. Physics Letters A. 2019,
383, 126004.
5. Hang Hu, Y.; Ruckenstein, E. Complexes of a bio-molecule and a C60 cage, J. Mol. Struct., Theochem. 2008, 850, 67–71.
6. Leon, A.; Jalbout, A.F.; Basiuk, V.A. Fullerene–amino acid interactions. A theoretical study, Chem. Phys. Lett. 2008, 452, 306–
314.
7. Leon, A.; Jalbout, A.F.; Basiuk, V.A. SWNT–amino acid interactions: a theoretical study, Chem. Phys. Lett. 2008, 457, 185–190.
8. Shahamirian, M,; Azami S.M.; Strong intramolecular hydrogen bonding in confined amino acids. Journal of Molecular Graphics
and Modelling. 2021, 106, 107913.
43
44. 9. Shi, J. et al. PEI-derivatized fullerene drug delivery using folate as a homing device targeting to tumor. Biomaterials. 2013, 34,
251-261.
10. Thotakura, N. et al. Aspartic acid derivatized hydroxylated fullerenes as drug delivery vehicles for docetaxel: an explorative
study. Artificial cells, nano medicine, and biotechnology. 2017, 46, 1763-1772.
11. Liu et al. Folic Acid Functionalized γ-Cyclodextrin C60, A Novel Vehicle for Tumor-Targeted Drug Delivery. J. Biomed.
Nanotechnol. 2016, 12, 1393–1403.
12. Kumar, V. Metal Encapsulated Clusters of Silicon: Silicon Fullerenes and other Polyhedral forms. Challenges and Advances in
Computational Chemistry and Physics. 2008, 24, 114-14.
44
DFT: Computational quantum mechanical modelling methodinvestigate molecular geometries and electronic structuresof a many-electron system by using functionalsThese functionals spatially depend on the electron density
%S character: Inverse relation with bond length
% S character: Direct relation with bond angle
Conventional HB is of electrostatic nature
Pharmacokinetics: study of pace of drug absorption, distribution, metabolism, and excretion.