Raman, Chandrasekhara

INDIAN PHYSICIST
1888–1970

Chandrasekhara Venkata Raman described himself as a "child of nature"; he was indeed a profound student of nature all his life, a keen and resourceful observer of the world around him. In addition to discovering the physical effect that bears his name, he can also be considered the father of modern Indian experimental science.

Raman was born near Trichinopoly (now Tiruchipalli) in southern India on November 7, 1888. His father, whose family had been farmers in the area for many generations, turned to teaching and became a lecturer in physics and mathematics at a small college in Vizagapatam when Raman was four years old. During Chandrasekhara's childhood, his father conveyed to him not only an interest in science but also a love of music. He attended Presidency College at the University of Madras, where he excelled in science and graduated in 1904 at the age of sixteen. Although his teachers urged him to go to England for graduate study, he was prevented from doing so for health reasons and remained at Presidency College to work on his master's, which he obtained in 1907. During this time Raman began his longtime interest in optical phenomena, publishing a paper in the Philosophical Magazine on the diffraction patterns of reflected light. At that time, modern scientific research was practically unknown in India, especially from someone who had not attended school outside the country.

Since there was scarce opportunity for Raman to pursue a scientific career when he graduated, he entered the civil service, becoming an accountant in the Indian Finance Department. During his ten years of service in this capacity, spent mostly in Calcutta, he continued to conduct scientific research under the auspices of the Indian Association for the Cultivation of Science, a small, privately endowed organization. Using simple and inexpensive equipment, and working outside his regular office hours, Raman published thirty papers in ten years, mostly in the area of sound. His work attracted the attention of the officers of the University of Calcutta, and in 1917 he was offered a professorship in physics, becoming the first Indianeducated scientist to hold such a post. He was then able to pursue his research more actively and to supervise graduate students.

While traveling to England in 1921 to attend a scientific congress, Raman was struck by the blue color of the Mediterranean Sea, caused by the scattering of sunlight in the clear water. This observation prompted the studies that culminated in his discovery of the characteristic changes in wavelength of scattered light caused by certain materials—the so-called Raman effect. Although previously predicted by others as a consequence of the interaction of light quanta with molecules, the actual effect was very weak and required long and careful measurements to establish. It represented a significant advance in chemical analysis, since at that time, other spectroscopic methods such as infrared spectroscopy were difficult and inexact without expensive instrumentation. On the contrary, only relatively simple equipment was necessary to observe the shifts in wavelength (the "Raman shifts") exhibited by a wide variety of chemical substances. Raman was knighted for this work in 1929 and received the Nobel Prize in physics in 1930, becoming the first Asian to receive the award.

Raman left Calcutta in 1933 to become the director of the Indian Institute of Science, in Bangalore, where he remained until 1948. He continued his research on optical and electromechanical phenomena but also worked on a wide range of problems that reflected his fascination with the natural world—diamonds, seashells, and the coloration of flowers and feathers. In 1948 he established the Raman Research Institute in Bangalore, where he continued to carry out research until almost the end of his life. He died on November 21, 1970.

see also Spectroscopy.

Bartow Culp

Bibliography

Bhagavantam, S. (1971). "Chandrasekhara Venkata Raman." Biographical Memoirs of the Royal Society 17: 565–592.

Krishnan, R. S., and Shankar, R. K. (1981). "Raman Effect: History of the Discovery." Journal of Raman Spectroscopy 10: 1–8.

Miller, F. A., and Kauffman, G. B. (1989). "C. V. Raman and the Discovery of the Raman Effect." Journal of Chemical Education 66: 795–801.

Venkataraman, G. (1988). Journey into Light. Bangalore: Indian Academy of Sciences.