C V Raman (Chandrasekhara Venkata Raman) was a Nobel Prize winner and a pioneering Indian physicist who made significant contributions to the fields of spectroscopy, optics, and related fields. He is known for his discovery of Raman scattering in 1922.
He introduced the concepts of wavenumber, energy level, and allowed mode in quantum mechanics. Raman’s work helped lay important foundations for understanding the atomic structure of matter by providing evidence that light consists of waves that exhibit both particle-like properties and wave-like properties.
About C V Raman
Raman was born in Sattur village, a small village in the South Arcot District of Madras Presidency (now Tamil Nadu).
He was educated at the Presidency College and Royal College, Madras. On completing his studies, he joined the Indian Civil Service (ICS), intending to work in the Revenue and Post Office Departments. But he soon realized that he lacked aptitude for administrative work and instead decided to switch to academic life by receiving a scholarship from the Government of India to pursue studies at the University of Toronto. He returned to Madras Presidency where he served as a professor of physics at Presidency College, succeeding C. V. Raman’s uncle K.
Personal life of C V Raman
V. Raman married Sarala Devi, with whom he had three sons and two daughters. He was married to S. Raman, who is the mother of his son, C. V. Seshadri Reddy (MBA 2008). His daughter Anitha married Kasturi Ranganatha Rao, the son of C P Raman (MBA 1974).
Achievements of C V Raman
He was awarded the Nobel Prize for Physics in 1930 for discovering that when light traverses a transparent material, some of the deflected light changes in wavelength. This phenomenon came to be called “Raman scattering”, and the effect became known as the “Raman Effect”. The discovery was made possible because of his invention of the “unequalled spectroscopic technique” where he suggested that light scattering measurements were most accurate when they were done on monochromatic light.
C V Raman did extensive research to prove that a beam of monochromatic light can result in different wavelengths.
He was appointed as a Reader at the Indian Institute of Science. Later became the Director of the Museum of Natural History. From 1919 to 1922, he did research on the magnetic properties of light, demonstrating that light scattering is an atomic phenomenon by illuminating molecules with monochromatic light from a gas-discharge lamp.
He demonstrated that when monochromatic light passes through any transparent material (e.g.: glass), part of the light is scattered at any internal interface present in the material. This phenomenon came to be known as “Raman scattering”. He followed this up with studies in 1923 on ‘The dispersion of white light into spectral colors. He named this phenomenon the “Spontaneous Raman Effect”. The phenomenon is also called the Raman Effect.
He was awarded the 1930 Nobel Prize in Physics for this work, which he shared with C.V.V. Lakshadweep. Later, he was made a Fellow of the Royal Society in 1920 and served as President of the Indian Physics Association from 1934 to 1936 and of the Optical Society of India from 1940 to 1943.
Raman did post-doctoral research at the University of Cambridge from 1923 to 1924 and returned to India in 1924. He was the first Indian professor at the Department of Physics, the Indian Institute of Science. He worked there from 1925 to 1928 and then again from 1930 to 1937.
In his later life, Raman shifted his focus to the study of plants that could increase agricultural and industrial productivity. He also developed methods to combat famine in India. This was based on earlier research he had done on identifying plants that could be useful as timber or as sources of chemical feedstock for the production of medicines, dyes, etc., and studying their distribution in India and other tropical countries.
Raman’s father, Venkata Subbiah, is credited with the establishment of a family business of selling nature-made products like pickles. After getting selected for the civil service examination and a stint at Presidency College, he joined the family business at 16 years of age with an interest in chemistry.
In his experiments, he found that when a beam of monochromatic light passes through an immovable obstacle (i.e., a long slit), some of the light is reflected backward through the same slit, with a small but finite angle to the original direction. This phenomenon came to be called “Raman scattering” and was later identified as the “Raman effect”.
He published these findings in Physical Review (now Physical Review Letters) in 1922, while he was undertaking his doctoral studies at the University of Cambridge, England.
The Blue color of the sea
In 1924, Raman paid a visit to the Indian Ocean near Penang, where he observed the phenomenon of blue color in the seawater. Raman returned to Penang in 1927. He completed the final volume of his book on Nature of Light published in 1925. He also started working on a more ambitious project to understand “the sea”.
Raman had started his studies by seeing red and green colors in liquid suspension (i.e., color as a function of wavelength). However, he was unable to identify any long-wavelength colored light source. In 1930, he visited the coasts of India between Calcutta and Madras and observed that water along the coasts had a bluish tone.
In June 1929, Raman presented a paper before the London-based Royal Society. He termed the phenomenon as “Colour of the Sea and Colour of Music”. Raman emphasized that color adds to the beauty. Therefore, he said that blue color was not found in land or plant sources. Which led him to conclude that the only source of light was the sun.
Raman noted that during twilight there was sufficient sunlight penetrating into the water to reflect back at night and give it a bluish tone. He also observed this phenomenon while crossing the Mahanadi River in a boat late at night. He realized that sound produced by musical instruments travels faster in solids than in liquids and gases and this phenomenon is responsible for propagating sounds better through solids.
Death of legend
C V Raman died on 21 November 1970 in Bangalore, India, aged 84 after a prolonged illness. He was cremated in Bangalore according to Hindu tradition. His ashes being interred by his wife at a memorial built in his honor at Begumpet village near Sattur in Tamil Nadu.
Chandrasekhara Venkata Raman won India’s first Nobel prize in the sciences. He received the award “for his work on scattered light and for the discovery of the effect named after him”. He shared the Nobel Prize with C. V. V. Lakshadweep, a colleague at the Indian Institute of Science.
Raman was elected a Fellow of the Royal Society on 27 March 1918. He served as president from 1957 to 1958. In 1924 he was appointed Director-General of Raman Research Institute in Mumbai, India. Raman was given credit for establishing this institution successfully in 1929, it is now known as Raman Research Institute (MRI). He was also appointed as an Honorary Director of the Indian Tobacco Board in 1931 to undertake research on genetics and tobacco varieties; while working there he made major contributions to understanding the biochemistry and physiology of tobacco leaves.