Successfully reported this slideshow.

Growth and spectroscopic studies on vitamin 'C' crystal


Published on

Published in: Education
  • Be the first to comment

  • Be the first to like this

Growth and spectroscopic studies on vitamin 'C' crystal

  1. 1. Growth and Spectroscopic Studies on Vitamin ‘C’ Crystal<br />S.N.Saravanamoorthy,<br /> Assistant Professor,<br /> Devanga Arts College (Autonomous),<br /> Aruppukottai – 626 101.<br /> Website :<br />
  2. 2. Crystal<br />* A crystal is a solid that has regularly repeating internal <br /> structure (arrangement of atoms).<br />* The basic “building block” in a crystal is called the unit cell.<br />* Most of the living beings form crystals. When the body fluids get<br /> supersaturated with minerals, crystallization takes place.<br />* These crystals have both beneficial as well as pathological <br /> effects on humans.<br />
  3. 3. Chemical Bonding in Solids<br />
  4. 4. Importance of Crystals<br />* Crystals find an important role in modern science and present day<br /> technology.<br />* Crystals are used in transducers, strain gauges, lasers and in<br /> polarizer etc.<br />* Crystalline films are used for microelectronic and computer <br /> technology. <br />* Crystals are a boon for the modern scientific development.<br />* In the recent years, direct visualization of nucleic acid and variety<br /> of proteins with which it interacts is possible by growing single<br /> crystals.<br />
  5. 5. Methods of Growing Crystals<br />The main categories of crystal growth methods are<br />1. Solid Growth<br />2. Melt Growth<br />3. Vapour Growth<br />4. Solution Growth<br />5. Gel Growth etc.,<br />
  6. 6. Solution Growth<br />* Crystal growth from solution occurs well below the melting point of the solid, thus minimizing the risk of thermal decomposition and giving low strain and dislocation content. <br />* The solution growth is feasible, whenever suitable solvent is available. <br />* The main disadvantage of this method is the incorporation of solvent into the crystals.<br />
  7. 7. Solution Growth<br />Low temperature High temperature<br />Slow cooling Slow evaporation Temperature gradient<br /> Flux growth Hydrothermal growth<br />
  8. 8. Present Work<br />* Vitamin ‘C’ crystal was grown by the slow<br /> evaporation method.<br />* The lattice parameters related to the grown<br /> crystal have been calculated using X-ray <br /> single crystal diffraction data.<br />* FT-IR spectra of the Vitamin ‘C’ compound<br /> has been recorded. <br />
  9. 9. Vitamins<br />*Vitamins are all organic chemicals.<br />* Vitamins are essential because the organism <br /> cannot synthesize these compounds, which<br /> are necessary for life.<br />* There are about 25 vitamins which have been<br /> arbitrarily classified into two types: <br /> 1) Fat soluble 2) Water soluble<br />
  10. 10. Vitamin ‘C’<br />* The original name was hexuronic acid, but this was changed to <br /> L(+)-ascorbic acid or vitamin ‘C’ because of its healing effect on <br /> scurvy.<br />* The chemical constitution was determined by Herbet, Hirst, <br /> Percival, Reynolds & Smith in 1933. <br />* It is closely related to the hexoses in structure and is conveniently <br /> synthesized from glucose. <br />* It is not a typical organic acid in that it has no free carboxyl group;<br /> actually a lactone structure is present.<br />
  11. 11. Structure of Vitamin ‘C’ compound<br />
  12. 12. Experimental Procedure<br />* L-ascorbic acid was weighed to 1.7614 gm and transferred into 50 ml <br /> beaker and 10 ml of distilled water was added to it and made it <br /> completely dissolved. It was transferred into Petri dish.<br />* The crystals were grown at room temperature by slow<br /> evaporation technique. <br />* The density of the crystal was measured by using Sink an Swim<br /> method (measured by flotation in a mixture of CCl4 & bromoform).<br />* Three dimensional intensity data were collected using Nonius<br /> Sealed tube MACH3 diffractometer.<br />
  13. 13. Crystallographic data, intensity data collection and <br />structure refinement parameters for the title compound<br />
  14. 14.
  15. 15. Bond lengths (Å) between various non-hydrogen atoms in the title compound<br />
  16. 16.
  17. 17. Bond angle (Å) between various non-hydrogen atoms in the title compound<br />
  18. 18.
  19. 19. Hydrogen bond lengths (Å) and angles (  ) <br />in the title compound<br />
  20. 20.
  21. 21. Spectroscopy<br />* Spectroscopy is the measurement and interpretation of <br /> absorption and emission of electromagnetic radiation when<br /> atoms or molecules or ions move from one energy level to <br /> another. <br />* There are various types of spectroscopic methods to analyze<br /> the molecular structures.<br />* Here, we have to use FT-IR spectroscopic methods to analyze<br /> the structure of Vitamin ‘C’ crystal.<br />
  22. 22. FT-IR Spectroscopy<br />*FT-IR spectroscopy first developed by astronomers in the <br /> early 1950 to study the IR spectra of distant stars.<br />* It is a measurement technique that allows one to record IR<br /> spectra.<br />* Infrared light is guided through an interferometer and further<br /> across the sample.<br />* The recorded signal is an interferogram that includes two <br /> contributions. One from the instrument itself, and another one<br /> due variations in “optical path difference” introduced by the <br /> sample. <br />
  23. 23. *Performing a Fourier transform on these two sets of data<br />(one with sample inserted, one without) results in spectra<br /> comparable to those obtained from a conventional (dispersive)<br /> infrared spectrometer.<br />* The effect due to the sample can be isolated by calculating the <br />ratio or the difference of the two spectra.<br />* The measurement is faster in FTIR technique because the <br /> information at all frequencies is collected simultaneously.<br />* Virtually all modern infrared spectrometers are FTIR instruments.<br />
  24. 24. Uses of FT-IR Spectroscopy<br />* Widely used in both research and industry.<br />* It is of especial use in forensic analysis in both criminal and civil<br /> cases, enabling identification of polymer degradation.<br />* Highly for applications in both organic and inorganic chemistry.<br />* It has been successfully utilized in the field of semiconductor<br /> microelectronics.<br />* FTIR is Used to study the events that occur at the blood-<br /> biomaterial interface.<br />* FTIR is now extensively used in areas such as toxicology, <br /> mutagenesis and general cellular research.<br />
  25. 25.
  26. 26. Spectral data (cm-1) and band assignments<br />* v, very; w, weak; m, medium; s, strong; sh, shoulder; b, broad.<br />
  27. 27. Conclusion<br />*The investigation of the Vitamin ‘C’ compound is important one<br /> because it acts as an electron donor for 11 enzymes and <br /> probably all of its biochemical and molecular roles can be <br /> accounted for by this function.<br />* The compound crystallites is the monoclinic space group P21.<br />* The molecular structure consists of intramolecular hydrogen <br /> bonds of type O-H…O.<br />* The wavenumber assignments have been made for the <br /> functional groups, viz. C=O, C=C, C-H, O-H, C-C, C-O, C-O-C,<br /> C-O-H, C-C(=O)-O.<br />