Carousel Previous Carousel Next. Organic Chemistry - Reactions and Mechanisms 1. Jump to Page. Search inside document. Mark Anthony Callus. Sandeep Kumar Thatikonda. Farooq Muhammad. Katipot Inkong. Edward Pitts. Loveena Steadman. Joey Shortino. Ankan Mukherjee. As per analytical science, every element or compound has a unique characteristic spectrum. Each compound absorbs and disperses light over a certain range of wavelengths.
Electromagnetic radiation is the continuous spectrum of energy-bearing waves ranging from extremely short waves, such as high-energy X-rays with wavelengths of about 10 nanometres [nm] , to very long, low-energy waves such as radio waves with wavelengths of one meter [m] or more.
Visible light, for example, is the range of electromagnetic radiation detectable by human vision, with wavelengths of roughly to nm. Objects appear colored when they absorb visible light of certain wavelengths, and those absorbed wavelengths are consequently absent from light that passes from the colored object to the eyes. Molecules are able to absorb light of certain wavelengths because the energy content of the absorbed light is the precise value needed to cause a molecule to be excited from one energy state to a higher one.
The myriad energy levels in a molecule are said to be quantized because each one differs from another by a discrete, measurable energy value, just as each step in a stairway is a fixed height above, or below, all others.
Thus, by measuring the wavelengths of the electromagnetic radiation absorbed by a molecule, it is possible to gain information about the various energy levels within it. The award of Nobel Prize in chemistry for to D. Cram, J. Lehn and C. Pedersen reflects the importance of topics mentioned above.
Keeping the significance of these areas in mind UGC has introduced these topics in the model curricula for Indian Universities at the postgraduate level. Ps Kalsi Spectroscopy. Kalsi PS. Spectroscopy of Organic Compounds 6th Edition P.
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