Introduction to Spectroscopy,
Introduction to UV, electronic transitions, terminology, chromophore, Auxochrome, Examples and Applications.
Introduction to IR, Fundamental vibrations, Types of Vibrations, Factors affecting the vibrational freaquencies, Group frequencies, examples and applications.
Nmr nuclear magnetic resonance spectroscopyJoel Cornelio
Basics of NMR. Suitable for UG and PG courses.
Includes principle, instrumentation, solvents. chemical shift and factors affecting it. Some problems. resolving agents, coupling constant and much more
Infrared spectroscopy (IR spectroscopy) is the spectroscopy that deals with the infrared
region of the electromagnetic spectrum, that is light with a longer wavelength and
lower frequency than visible light.
Infrared Spectroscopy is the analysis of infrared light interacting with a molecule.
IR SPECTROSCOPY, INTRODUCTION, PRINCIPLE, THEORY, FATE OF ABSORBED RADIATION, FERMI RESONANCE, FINGERPRINT REGION, VIBRATIONS, FACTORS AFFECTING ABSORPTION OF IR RADIATION, SAMPLING TECHNIQUES, APPLICATIONS OF IR SPECTROSCOPY.
Nmr nuclear magnetic resonance spectroscopyJoel Cornelio
Basics of NMR. Suitable for UG and PG courses.
Includes principle, instrumentation, solvents. chemical shift and factors affecting it. Some problems. resolving agents, coupling constant and much more
Infrared spectroscopy (IR spectroscopy) is the spectroscopy that deals with the infrared
region of the electromagnetic spectrum, that is light with a longer wavelength and
lower frequency than visible light.
Infrared Spectroscopy is the analysis of infrared light interacting with a molecule.
IR SPECTROSCOPY, INTRODUCTION, PRINCIPLE, THEORY, FATE OF ABSORBED RADIATION, FERMI RESONANCE, FINGERPRINT REGION, VIBRATIONS, FACTORS AFFECTING ABSORPTION OF IR RADIATION, SAMPLING TECHNIQUES, APPLICATIONS OF IR SPECTROSCOPY.
A complete and comprehensive presentation on UV-VISIBLE SPECTROSCOPY.
The purpose of making, uploading these presentations for understanding for both the students and the teachers.
Each and every topic is arranged in series.
Slide by slide the topic should be covered to make your concepts Strong.
ir spectroscopy: introduction modes of vibration, selection rule, factor, influcing of vibration, scaning of ir spectroscopy(instrumentation) vibration frequency of organic and inorganic compound
Introduction
Instrumentation
Sampling techniques
Group frequencies
Factors affecting group frequencies
Complementarity of IR and Raman spectroscopy
Applications of Infrared spectroscopy
Communication in Insects.
Classification of Semiochemicals.
Introduction to Insect Pheromones.
Uses of Insect Pheromones.
Synthesis of Insect Pheromones.
Use of pheromones in insect pest management.
DRUG DISCOVERY
Drug Discovery without a lead
LEAD DISCOVERY/IDENTIFICATION
LEAD MODIFICATION
CONCEPT OF PRODRUGS AND SOFT DRUGS
DRUG RECEPTOR INTERACTIONS
TLC-Introduction, Principle, Procedure, and Applications.
Paper Chromatography-Introduction, Principle, Procedure, and Applications.
Column Chromatography-Introduction, Principle, Procedure, and Applications.
Introduction, Basic Principles, Terminology, Instrumentation, Ionization techniques (EI, CI, FAB, MALDI, and ESI), Mass Analyzer (Magnetic sector instruments, Quadrupole, TOF, and ICR ), and Applications of Mass Spectrometry.
Applications of Infrared spectroscopy
Identification of organic compounds,
Structure determination
Qualitative analysis of functional group
Quantitative analysis
Distinction between two types of hydrogen bonding
Study of chemical reaction
Study of Keto-Enol tautomerism
Conformational analysis
Geometrical isomerism
Study of complex molecules
Detection of impurity in a compound
Identification of the organic compounds by IR
Hydrocarbons, Aromatic compounds, Alcohol, Phenols, Ethers, Aldehydes, Ketones, Esters, Acid chlorides, Anhydrides, Amides, Amines, Nitriles, Isocynates, Isothiocynates, Imines and Nitro compounds.
Introduction,Instrumentation, Classification of electronic transitions, Substituent and solvent effects, Classification of electronic transitions
Substituent and solvent effects
Applications of UV Spectroscopy
UV spectral study of alkenes
UV spectral study of poylenes
UV spectral study of α, β-unsaturated carbonyl
UV spectral study of Aromatic compounds
Empirical rules for calculating λmax.
Applications of UV Spectroscopy, Empirical rules for calculating λmax.
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
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.
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In this book, we use conservation of energy techniques on a fluid element to derive the Modified Bernoulli equation of flow with viscous or friction effects. We derive the general equation of flow/ velocity and then from this we derive the Pouiselle flow equation, the transition flow equation and the turbulent flow equation. In the situations where there are no viscous effects , the equation reduces to the Bernoulli equation. From experimental results, we are able to include other terms in the Bernoulli equation. We also look at cases where pressure gradients exist. We use the Modified Bernoulli equation to derive equations of flow rate for pipes of different cross sectional areas connected together. We also extend our techniques of energy conservation to a sphere falling in a viscous medium under the effect of gravity. We demonstrate Stokes equation of terminal velocity and turbulent flow equation. We look at a way of calculating the time taken for a body to fall in a viscous medium. We also look at the general equation of terminal velocity.
Salas, V. (2024) "John of St. Thomas (Poinsot) on the Science of Sacred Theol...Studia Poinsotiana
I Introduction
II Subalternation and Theology
III Theology and Dogmatic Declarations
IV The Mixed Principles of Theology
V Virtual Revelation: The Unity of Theology
VI Theology as a Natural Science
VII Theology’s Certitude
VIII Conclusion
Notes
Bibliography
All the contents are fully attributable to the author, Doctor Victor Salas. Should you wish to get this text republished, get in touch with the author or the editorial committee of the Studia Poinsotiana. Insofar as possible, we will be happy to broker your contact.
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We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
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30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
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M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
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at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
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Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
BLOOD AND BLOOD COMPONENT- introduction to blood physiology
Basic Concepts of UV & IR Spectroscopy
1. BASIC CONCEPTS OF UV-VISIBLE AND
IR SPECTROSCOPY
DR. BASAVARAJAIAH S. M.
M. SC., PH.D.
COORDINATOR
PG DEPARTMENT OF CHEMISTRY
VIJAYA COLLEGE
BENGALURU-560004.
drsmbasu@gmail.com
2. Spectroscopy
Spectroscopy is a general term referring to the interactions
of various types of electromagnetic radiation with matter.
Exactly how the radiation interacts with matter is directly
dependent on the energy of the radiation.
4. Electromagnetic radiation displays the properties of both particles
and waves.
The particle component is called a photon.
The energy (E) component of a photon is proportional to the
frequency . Where h is Planck’s constant and n is the frequency in
Hertz (cycles per second).
E = hν
The term “photon” is implied to mean a small, massless particle
that contains a small wave-packet of EM radiation/light-we will use
this terminology in the course.
5. Spectroscopy
The higher energy ultraviolet and visible wavelengths affect the
energy levels of the outer electrons.
Radio waves are used in nuclear magnetic Resonance and affect
the spin of nuclei in a magnetic field.
Infrared radiation is absorbed by matter resulting in rotation
and/or vibration of molecules.
6. Ultraviolet radiation stimulates molecular vibrations and
electronic transitions.
Absorption spectroscopy from 160 nm to 780 nm.
Measurement absorption or transmittance.
Identification of inorganic and organic species.
UV-Vis Spectroscopy
7. UV/VIS SPECTROSCOPY
Ultraviolet (UV) (10 – 380 nanometers).
Visible (380-780 nanometers).
Below about 200 nm, air absorbs the UV light
and instruments must be operated under a vacuum
8. Electronic transitions
The absorption of UV or visible radiation corresponds to the
excitation of outer electrons. There are three types of electronic
transition which can be considered;
Transitions involving σ, π, and n electrons.
Transitions involving charge-transfer electrons.
Transitions involving d and f electrons.
CLASSIFICATION OF ELECTRONIC TRANSITIONS
13. Bathochromic Shift or Red shift: A shift of an
absorption maximum towards longer wavelength (λ) or
lower energy (E).
Hypsochromic Shift or Blue Shift: A shift of an
absorption maximum towards shorter wavelength (λ)
or higher energy (E).
Hyperchromic Effect: An effect that results in increased
absorption intensity (ε).
Hypochromic Effect: An effect that results in decreased
absorption intensity (ε).
Terminology in UV:
14.
15. Wavelengths Absorbed by Functional Groups
Again, demonstrates the moieties contributing to absorbance from
200-800 nm, because π electron functions and atoms having no
bonding valence shell electron pairs.
25. Which of the following alkenes would have the largest λmax?
26. Which molecule absorbs at the longest wavelength, 1,3-hexadiene
or 1,4-hexadiene?
Why the λmax for the diene (I) is observed at lower nm than (II).
(I) (II)
29. INTRODUCTION
Infra-red spectrum is an important record which gives sufficient
information about the structure of a compound.
IR electromagnetic radiation is just less energetic than visible light.
The infrared spectral regions are as follows.
The absorption of Infra-red radiations (quantized) causes the
various bands in a molecule to stretch and bend with respect to one
another.
30. The frequency of IR radiation is commonly expressed in wave
numbers.
Wavenumber (ῡ): The number of waves per centimeter, cm-1 (read
reciprocal centimeters).
Expressed in wavenumbers, the vibrational IR extends from 4000
cm-1 to 670 cm -1
.
Convert a wavenumber (ῡ) to a frequency (υ) by multiplying it by
the speed of light.
The main reason chemists prefer to use wave numbers as units is
that they are directly proportional to energy.
Wavenumber (ῡ) = 1/ Frequency (υ) = c/
31. USES OF THE INFRARED SPECTRUM
Fingerprint region:
The 1500-600 cm-1 range of an infrared spectrum, called the fingerprint
region because (like a human fingerprint) this region of the spectrum is
almost unique for any given compound.
Functional group region:
The functional group region runs from 4000 cm-1 to 1500 cm-1.
32.
33. To locate a point in three-dimensional space requires three coordinates.
To locate a molecule containing N atoms in three dimensions, 3N
coordinates are required. The molecule is said to have 3N degrees of
freedom.
To describe the motion of such a molecule, translational, rotational, and
vibrational motions must be considered.
In a nonlinear molecule:
3 of these degrees are rotational and 3 are translational and the
remaining correspond to fundamental vibrations;
In a linear molecule: (Linear molecules cannot rotate about the bond axis)
2 degrees are rotational and 3 are translational.
The net number of fundamental vibrations:
THEORETICAL VIBRATIONAL NORMAL MODES
34. Ethane, C2H6 has eight atoms (N=8) and is a nonlinear molecule so
of the 3N=24 degrees of freedom, three are translational and three
are rotational. The remaining 18 degrees of freedom are internal
(vibrational). This is consistent with:
3N−6=3(8)−6=18
Carbon Dioxide, CO2 has three atoms (N=3) and is a linear
molecule so of the 3N=9 degrees of freedom, three are translational
and two are rotational. The remaining 4 degrees of freedom are
vibrational. This is consistent with:
3N−5=3(3)−5=4
35. THE MODES OF VIBRATION: STRETCHING AND BENDING
The simplest types, or modes, of vibrational motion in a molecule
that are infrared active-those, that give rise to absorptions-are the
stretching and bending modes.
Stretching vibration involves a continuous change in the inter-
atomic distance along the axis of the bond between two atoms. These
are two types; Symmetric and Asymmetric Stretching.
Bending vibrations are characterized by a change in the angle
between two bonds and are of four types: Scissoring, Rocking,
Wagging and Twisting.
36. Stretching frequencies are higher than corresponding bending
frequencies.
Symmetric and Asymmetric Stretching Vibrations
Symmetrical stretching: The atoms of a molecule either move away
or towards the central atom, but in the same direction.
Asymmetric stretching: One atom approach towards the central
while other departs from it.
37. BENDING VIBRATIONS
Scissoring is the movement of two atoms toward and away from
each other.
Rocking is like the motion of a pendulum on a clock, but an atom is
the pendulum and there are two instead of one.
Wagging is like the motion in which you make a "V" sign with your
fingers and bend them back and forth from your wrist.
Twisting is a motion as if the atoms were walking on a treadmill.
39. VIBRATIONAL MODES OF H2O (3 ATOMS –NON LINEAR)
Vibrational modes (degrees of freedom) = 3 x 3 - 6= 3
These normal modes of vibration:
are a symmetric stretch, and asymmetric stretch, and a scissoring
(bending) mode.
40. Fundamental Vibrational modes = 3 x 3-5 = 4.
FUNDAMENTAL VIBRATIONAL MODES OF CO2 (3 ATOMS –LINEAR)
41. Let us now consider how bond strength and the masses of the
bonded atoms affect the infrared absorption frequency.
The natural frequency of vibration of a bond is given by the
equation (Hooke’s law).
VIBRATIONAL FREQUENCY
42. A new expression is obtained by inserting the actual values of π and
c:
Examples:
Note: Vibrational frequency is directly proportional to force constant
(K) (Bond strength) and inversely proportional to reduced mass (μ).
43. In general, triple bonds are stronger than double or single bonds
between the same two atoms and have higher frequencies of vibration
(Higher wavenumbers):
The C-H stretch occurs at about 3000 cm-1. As the atom bonded to
carbon increases in mass, the reduced mass (μ) increases, and the
frequency of vibration decreases (wavenumbers get smaller):
44. Bending motions occur at lower energy (lower frequency) than the
typical stretching motions because of the lower value for the bending
force constant K.
Hybridization affects the force constant K, also. Bonds are stronger in
the order sp>sp2>sp3, and the observed frequencies of C-H vibration
illustrate this nicely.
47. Factors affecting group frequencies
The value of vibrational frequency of a bond calculated by Hooke’s
Law is not always equal to their observed value.
The force constant is changed with the electronic and steric effects
caused by other groups present in the surroundings.
Following are some important factors affecting the vibrational
frequency of a bond.
Effect of Bond Order
Bond order affects the position of absorption bands. Higher the bond
order larger is the band frequency.
A C-C triple bond is stronger than a C=C bond, so a C-C triple bond
has higher stretching frequency than does a C=C bond.
48. Similarly, a C=O bond stretches at a higher frequency than does a C-O
bond and a C-N triple bond stretches at a higher frequency than does a
C=N bond which in turn stretches at a higher frequency than does a C-N
bond.
49. Electronic Effects:
Changes in the absorption frequencies for a particular group take place when the
substituent's in the neighbourhood of that particular group are changed.
The frequency shifts are due to the electronic effects which include Inductive
effect, Mesomeric effect, Field effects etc.
Under the influence of these effects, the force constant or the bond strength
changes and its absorption frequency shifts from the normal value.
The introduction of alkyl group causes +I effect which results in the lengthening
or the weakening of the bond and hence the force constant is lowered and
wavenumber of absorption decreases.
Wavenumber of νC=O Formaldehyde (HCHO) 1750 cm-1
Acetaldehyde (CH3CHO) 1745 cm-1
Acetone (CH3COCH3) 1715 cm-1
Note: Aldehydes absorb at higher wavenumber than ketones
50. The introduction of an electronegative atom or group causes –I effect
which results in the bond order to increase.
Thus, the force constant increases and hence the wavenumber of
absorption rises.
Wavenumber of νC=O Acetone (CH3COCH3) 1715 cm-1
Chloroacetone (ClCH2COCH3) 1725 cm-1
Dichloroacetone (Cl2CHCOCH3) 1740 cm-1
Conjugation lowers the absorption frequency of C=O stretching whether
the conjugation due to α, β-unsaturation or due to an aromatic ring.
O
O
Methyl vinyl ketone Acetophenone
νC=O 1706 cm-1 1693 cm-1
Note: -I effect is dominated by mesomeric effect.
51. The electron pair on nitrogen atom in amide is more labile and participates more in
conjugation, hence the amide absorbs less frequency than the esters.
The lone pair of electrons participates more in conjugation in compound I as
compared to that compound III. Thus, in compound I, ν(C=O) absorption occurs at
lower wave number compared to that in compound III. In compounds II and IV,
inductive effect dominates over mesomeric effect and hence absorption takes place
at comparatively higher frequencies.
52. Hydrogen Bonding
The presence of hydrogen bonding changes the position and shape of
an infrared absorption band.
Frequencies of both stretching as well as bending vibrations are
changed because of hydrogen bonding.
The X-H stretching bands move to lower frequency usually with
increased intensity and band widening. The X-H bending vibration
usually shifts to higher frequencies.
Stronger the hydrogen bonding, greater is the absorption shift towards
lower wavenumber from the normal values.
The two types of hydrogen bonding (intramolecular and
intermolecular) can be differentiated by the use of infrared
spectroscopy.
53. The extent of inter-molecular hydrogen bonding depends upon the concentration of
the solution and hence the position and the shape of an absorption band also depend
on the concentration of the solution.
The more concentrated the solution, the more likely it is for the OH-containing
molecules to form intermolecular hydrogen bonds. It is easier to stretch an O-H bond
if it is hydrogen bonded, because the hydrogen is attracted to the oxygen of
neighbouring molecule.
Therefore, the O-H stretching of a concentrated (hydrogen bonded) solution of an
alcohol occurs at about 3550 cm-1, whereas the O-H stretching band of a dilute
solution (with little or no hydrogen bonding) appears at 3650 cm-1 .
Additionally, hydrogen-bonded OH groups also have broader absorption bands
whereas the absorption bands of non-hydrogen–bonded OH groups are sharper.
54. Field effect:
In ortho substitution, inductive effect, mesomeric effect along with steric
effect is considered. In ortho substituted compounds, the lone pairs of
electrons on two atoms influence each other through space interactions and
change the vibrational frequencies of both the groups. This effect is called
field effect.
The non-bonding electrons present on oxygen atom and halogen cause electrostatic
repulsions. This causes a change in the C=O hybridization and which in turn makes it
to go out of plane of the double bond.
Thus, the conjugation is diminished and absorption occurs at a higher wavenumber.
Thus, for such ortho substituted compounds, cis absorbs (field effect) at a higher
frequency as compared to the trans isomer.
55. Bond angles
Smaller ring requires the use of more p-character to make the
internal C-C bonds for the requisite small angles.
This gives more s character to the C=O sigma bond which causes the
strengthening and stiffening of the exocyclic double bond. The force
constant K is then increased and the absorption frequency increases.
56. Complementarity of IR and Raman spectroscopy
For the infra-red spectrum to occur, the molecule must show a
change in the dipole moment. For the Raman spectra, there must be
a polarstability of the molecule.
As these two requirements are somewhat different, lines may be
formed in one of the spectra or in both. The symmetrical stretching
of the molecule which are usually missing in the infra-red appear
prominently in Raman spectra.
On the other hand, asymmetric vibrations show opposite behavior.
Thus, we say that vibrational modes which are inactive in Infra-red
are somewhat active in Raman spectra.
57. For carbon dioxide, the bending and antisymmetric modes are infrared active, while
the symmetric stretch mode is Raman active. This behaviour is typical of all
centrosymmetric molecules. Modes that are infrared active are Raman inactive and
vice versa.
This is the Rule of Mutual Exclusion, which states that no normal mode can be both
infrared and Raman active in a molecule that possesses a centre of symmetry.
Rule of Mutual Exclusion:
71. Applications of IR spectroscopy
Identification of organic compounds
Structure determination
Qualitative analysis of functional group
Distinction between two types of hydrogen bonding
Quantitative analysis
Study of chemical reaction
Study of Keto-Enol tautomerism
Study of complex molecules
Detection of impurity in a compound.