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RAMAN, Chandrasekhara Venkata*
Founding Fellow, President: 1934-70
b. 7 November 1888, Trichinopoly, Tamil Nadu
d. 21 November 1970
s. R Chandrasekara Iyer and Parvati Ammal
m. Lokasundari, two s
Edn.: Univ. of Madras: BA 04, MA 07; Hon. doctorates from
17 Univs. in India and abroad. Career: Indian Finance Dept.,
Calcutta and Rangoon: Gazetted Offr. 07-17; Univ. of Calcutta:
Palit Professor-ship 17-33; IACS, Calcutta: Research 07-33
and Hon. Secy. 19--32; IISC, Bangalore: Director 33-38, Prof.
of Phys. 33-48, RRI, Bangalore: Founder-Director 48-70. Fellow,
Royal Soc. of London, INSA; Hon. Fellow, Optical Soc. of America,
Mineralogical Soc. of America; Foreign Associate, Paris Acad.
of Sc.; Foreign Member, USSR Acad. of Sc.; Hon. Member Acad.
of the Republic of Romania and Catgut Acoustical Soc. (a renowned
group of violinists); General President, Indian Science Congress
29. Curzon Res. Prize 12; Woodburn Res. Medal 13; Matteucci
Medal 28; Knighted by the British Govt. 29; Hughes Medal of
the Royal Soc. of London 30; Nobel Prize for Physics 30; Rajasabhabhushana
by the Mysore Maharaja 35; Franklin Medal of Franklin Institute
41; National Professor 48; Bharat Ratna 54; Lenin Prize, USSR
57. Sc. Work in Vibrations and Musical Instruments, Geometrical
and Wave Optics, Light and X-ray Scattering, Physics of Crystals,
Colour. Best known for the Phenomenon of inelastic light scattering
named the 'Raman effect' after him. Large body of experimental
work was concerned with waves - wave motions of vibrating
strings, sound waves, notes of musical instruments, wave optics:
diffraction and interference effects. For this and other work
simple but cleverly devised apparatus was designed and fabricated
jointly with co-workers. Early examples are the arrangement
to obtain photographs of the movement of nodes in a vibrating
string and the mechanical violin player used to study. the
mechanics of bowing of violin strings. Made detailed studies
of the Dynamics of sound production of Indian stringed and
percussion musical instruments. His concern with scattering
of light by molecules of substances began in 1919 at IACS,
and culminated in the paper published with K. S. Krishnan,
in Nature in 1928. It announced the discovery of 'a new type
of secondary radiation' later identified to be the result
of a particular kind of light scattering that received the
name 'Raman effect'. Honored with the Nobel prize in physics
in 1930 for this discovery. Early work in optics at IACS included
studies on diffraction fringes, caustics, halos, interference
rings, and optical anisotropy and birefringence. While steeped
in classical physics, was apparently conscious of other emerging
trends, thus, with K. R. Ramanathan he proposed one of the
first theories of X-ray diffraction in liquids and deduced
that the theory of light scattering due to density fluctuations
in gases. This theory could be applied to X-ray scattering
also at small angles of scattering. It spurred some early,
if rudimentary, work by the IACS group on X-ray diffraction
by many substances, including some of biological interest.
Later work in optics at IISC and RRI dealt with iridescence
in stratified media, including natural materials such as bird
plumage and marine shells, and ancient glass; coronae and
halos; more interference rings; optics of heterogeneous media;
colour; and studies on minerals and gems, including diamond.
Three pieces of work in this period, considered important
landmarks or forerunners of later, more precise work by others,
are the investigations with N. S. Nagendra Nath, of the diffraction
of light by density, fluctuations in a liquid produced by
an ultrasonic wave. The discovery with T. M. K. Nedungadi,
of a soft mode in quartz, with G. N. Ramachandran, a quantitative
description in terms of interference effects of the diffusion
corona due to randomly distributed particles (later called
the speckle phenomenon) and over thirty years with a series
of collaborators, S. K. Mitra, S. K. Banerji, K. S. Krishnan,
Y. V. Kathavate and others, developed a versatile geometric
theory of Fresnel dif-fraction. In a series of investigations
on diamond attempted to formulate new rules of crystal symmetry
for diamond but was later proven wrong. Was involved at this
time in a deep controversy with Max Born concerning the Dynamics
of crystal lattices. While Raman's theory was later shown
to be wrong, it nevertheless predicted significant vibrational
frequencies of crystal lattices observed in experiments because
it gave an important subset of the modes in Born's theory.
Published about 450 research papers and guided a large number
of research students, many of whom went into scientific eminence
and achievement in their own right.
Last Address: Raman Research Institute, Bangalore 560 080.
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