National Science Day: Raman effect and all you need to know about the man who discovered it

National Science Day is celebrated with great enthusiasm on 28 February to commemorate the discovery of Raman Effect on the same day in 1928 by Indian physicist and Nobel Laureate Sir Chandrasekhara Venkata Raman in India.

The day is celebrated as one of the prominent science fests in India every year, during which students of various schools and colleges demonstrate motley of science projects and national and state science institutions exhibit their latest researches. The occasion is also o widely spread a message about the significance of scientific applications in the daily life of the people.

C V Raman

File image of CV Raman. Wikimedia Commons

The then Central government was asked to honour this event always in the future by the National Council for Science and Technology Communication (NCSTC) in the year 1986. According to space-india.com, every year NCSTC announces a new theme to celebrate.

In the spirit of this day, New Delhi-based Science Popularisation Association of Communicators and Educators (SPACE) organisation conducts various science related activities involving public, school and college students.

Theme of the year

This year's theme is 'Science and technology for specially-abled persons', in accordance with which New Delhi-based Science Popularisation Association of Communicators and Educators (SPACE) organisation will take skill development classes — air rocket construction and launching, weigh yourself on different planets, catch the meteors, ring the planet, astronaut can you be one, take a picture as an astronaut and dress as an alien and astronaut, the organisation said in a statement on Monday.

Children and youngsters — from the Asthavakra School, Rohini; Sparsh Foundation, Kalyan Vihar and Model Town in Delhi; Nirdosh School, Sarbha Nagar in Ludhiana and Sankalp-Open School and Learning Centre in Chennai, will participate in the initiative by SPACE.

The organisation also conducts various science related activities with public, school and college students and have successfully organised various programmes such as Astronomy fairs and competitions with the objective to create enthusiasm among people and to inculcate scientific temper among the masses.

Physically and visually impaired children and youngsters in Delhi, Ludhiana and Chennai will get an opportunity to learn various aspects of astronomy as part of the National Science Day celebrations in the country, SPACE said on Monday.

Life of Sir CV Raman 

According to Nobel.org, Chandrasekhara Venkata Raman was born at Tiruchirappalli in Southern India on 7 November 1888. His father was a lecturer in mathematics and physics so that from the first he was immersed in an academic atmosphere. He entered Presidency College, Madras, in 1902, and in 1904 passed his BA examination, winning the first place and the gold medal in physics; in 1907 he gained his MA degree, obtaining the highest distinctions.

His earliest researches in optics and acoustics — the two fields of investigation to which he has dedicated his entire career — were carried out while he was a student.

Since at that time a scientific career did not appear to present the best possibilities, Raman joined the Indian Finance Department in 1907; though the duties of his office took most of his time, Raman found opportunities for carrying on experimental research in the laboratory of the Indian Association for the Cultivation of Science at Calcutta (of which he became Honorary Secretary in 1919).

In 1917, he was offered the newly endowed Palit Chair of Physics at Calcutta University, and decided to accept it. After 15 years in Calcutta, he became Professor at the Indian Institute of Science at Bangalore (1933-1948), and since 1948 he was the director of the Raman Institute of Research at Bangalore, which was established and endowed by him. He also founded the Indian Journal of Physics in 1926, of which he is the Editor. Raman sponsored the establishment of the Indian Academy of Sciences and has served as President since its inception. He also initiated the proceedings of that academy, in which much of his work has been published, and is President of the Current Science Association, Bangalore, which publishes Current Science (India).

Raman's accomplishments

Nobel.org says that some of Raman's early memoirs appeared as Bulletins of the Indian Association for the Cultivation of Science. In 1922 he published his work on the "Molecular Diffraction of Light", the first of a series of investigations with his collaborators which ultimately led to his discovery, on the 28th of February, 1928, of the radiation effect which bears his name and which brought him the 1930 Nobel Prize in Physics.

Other investigations carried out by Raman were: His experimental and theoretical studies on the diffraction of light by acoustic waves of ultrasonic and hypersonic frequencies (published 1934-1942), and those on the effects produced by X-rays on infrared vibrations in crystals exposed to ordinary light. In 1948 Raman, through studying the spectroscopic behaviour of crystals, approached in a new manner fundamental problems of crystal dynamics. His laboratory has been dealing with the structure and properties of diamond, the structure and optical behaviour of numerous iridescent substances (labradorite, pearly felspar, agate, opal, and pearls).

Among his other interests have been the optics of colloids, electrical and magnetic anisotropy, and the physiology of human vision.

Raman has been honoured with a large number of honorary doctorates and memberships of scientific societies. He was elected a Fellow of the Royal Society early in his career (1924), and was knighted in 1929.

Raman Effect 

According to Britannica.com, Raman effect, change in the wavelength of light that occurs when a light beam is deflected by molecules. When a beam of light traverses a dust-free, transparent sample of a chemical compound, a small fraction of the light emerges in directions other than that of the incident (incoming) beam. Most of this scattered light is of unchanged wavelength. A small part, however, has wavelengths different from that of the incident light; its presence is a result of the Raman effect.

 (with inputs from the agencies)

Published Date: Feb 28, 2017 03:42 pm | Updated Date: Feb 28, 2017 03:48 pm