Raman Effect

Raman Effect : Raman scattering  or the  Raman effect  (  /? r m? n/) is the  inelastic scattering  of a  photon. It was discovered by  Sir Chandrasekhara Venkata Raman  and  Kariamanickam Srinivasa Krishnan  in liquids,[1]  and by  Grigory Landsberg  and  Leonid Mandelstam  in crystals. [2][3] When  light  is  scattered  from an  atom  or  molecule, most  photons  are  elastically scattered  (Rayleigh scattering), such that the scattered photons have the same energy (frequency) and  wavelength  as the incident photons.However, a small fraction of the scattered light (approximately 1 in 10 million photons) is scattered by an excitation, with the scattered photons having a frequency different from, and usually lower than, the frequency of the incident photons. [4]  In a gas, Raman scattering can occur with a change in vibrational or rotational energy of a molecule (see  energy level). Chemists are concerned primarily with t he vibrational Raman effec Hargobind Khorana :   Indian-bornAmerican  biochemist who shared the  Nobel Prize in Physiology or Medicine  in 1968 with  Marshall W.Nirenberg  andRobert W. Holley  for research that helped to show how the  nucleotides  in  nucleic acids, which carry the  genetic code  of the cell, control the cell’s synthesis of proteins. Subramanian Chandrasekhar: was an  Indian  astrophysicist  who, with  William A. Fowler, won the 1983Nobel Prize for Physics  for key discoveries that led to the currently accepted theory on the later evolutionary stages of massive stars. [3][4]  Chandrasekhar was the nephew of  Sir Chandrasekhara Venkata Raman, who won the Nobel Prize for Physics in 1930.J. C Bose : was a  Bengali  polymath: a  physicist,  biologist,  botanist,  archaeologist, as well as an early writer of  science fiction. [5]  He pioneered the investigation of  radio  and  microwave  optics, made ve ry significant contributions to  plant science, and laid the foundations of  experimental  science  in the  Indian subcontinent. [6]  IEEE  named him one of the  fathers  of  radio  science. [7]  He is also considered the father of  Bengali science fiction. He was the first person from the  Indian subcontinent  to receive a  US patent, in 1904.