In the light of the equation of motion method a general expression for polarisability calculation has been derived. From this general expression, different approximation methods can be deduced for different choices of ground state and excitation manifold. Among these the coupled Hartree-Fock theory is the most extensively used one for polarisability calculations. It has also been shown that this theory has a simple relationship with random phase approximation. © 1984 Indian Academy of Sciences.

M GUPTA

S BHATTACHARYYA

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

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The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

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It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

On the calculation of second order properties: An equation of motion approach

Pramana

The static polarizability of fifteen organic molecules (point group symmetry: C2v; number of electrons ≥ 26) have been theoretically calculated using the CNDO/S-CHFT scheme and the results have been compared with other available data. © 1986, Indian Academy of Sciences. All rights reserved.

Journal	Data powered by TypesetPramana
Publisher	Data powered by TypesetSpringer India
ISSN	0304-4289