Raman, Sir Chandrasekhara

Raman, Sir Chandrasekhara Venkata (1888-1970), the Indian scientist, discovered the phenomenon in 1928 while studying CCI4 he was awarded the Nobel Prize in Physics in 1930. 

The Indian physicist Sir Chandrasekhara Venkata Raman was on a cruise on the Mediterranean Sea in 1921. Some reports suggest it was his honeymoon. Others say the beauty of its deep blue opalescence captivated him. Whatever the reason, he dedicated the rest of his life to understanding its colour and discovered the so-called Raman effect. 

Raman effect /rah-man/ A change in the frequency of electromagnetic radiation that occurs when a photon of radiation undergoes an inelastic collision with a molecule. The effect was first observed by the Indian physicists Sir Chandrasekhara Venkata Raman (1888-1970) and his colleague Sir Kariamanikkam Srinivasa Krish-nan in 1928. It has been used extensively in Raman spectroscopy for the determination of molecular structure, particularly since the advent of the laser. 

Although the Raman effect was discovered in 1928 by Sir Chandrasekhara Venkata Raman, it has not until recently been applied to food adulteration problems (Baeten et al., 1996 Li-Chan, 1994 Ozaki et aL, 1992 Sadeghi-Jorabchi et al., 1990, 1991). Baeten et al. (1996) used FT-Raman which, they claim, produces fluorescence-free spectra, using a 1.064 pm laser. They were able to detect adulteration with soybean, corn and olive pomace with 100% accuracy down to 1% adulterant. In fact 780 nm excitation in a confocal instrument (Williams, 1994 Williams et al., 1994) produces excellent dispersive Raman spectra from olive oils in a wholly non-invasive fashion (N. Kaderbhai and the authors, unpublished observations). Baeten et al. (1996) comment that at present liquid and gas chromatography is the most accurate technique to determine adulteration, and it is this method that is the European Union adulteration standard (EC, 1991), but that FT-Raman has the potential for detecting adulterants beyond the limits of liquid and gas chromatography. 

Sir Chandrasekhara Venkata Raman, the winner of the Nobel Prize in Physics in 1930, was so confident that his discovery of Raman scattering would win him the prize that he booked tickets to Stockholm even before the award winners were announced. 

Fig. 4.4 Mario Betti (left) shown in his senatorial robes at the University of Bologna, ca. 1937. To his left 1930 Nobel Laureate for physics, Sir Chandrasekhara Raman (1888-1970), A. Ghigi (1875-1970), Rector of the university in his Fascist uniform, and G.B. Bonino (1899-1985)...

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