Next Article in Journal
Next Article in Special Issue
Previous Article in Journal
Previous Article in Special Issue
Int. J. Mol. Sci. 2002, 3(6), 710-732; doi:10.3390/i3060710
Article

Higher Energy Derivatives in Hilbert Space Multi-Reference Coupled Cluster Theory : A Constrained Variational Approach

 and *
Received: 18 December 2001; Accepted: 10 April 2002 / Published: 30 June 2002
(This article belongs to the Special Issue Multireference Quantum Chemical Methods)
Download PDF [151 KB, uploaded 19 June 2014]
Abstract: In this paper, we present formulation based on constrained variational approach to compute higher energy derivatives upto third order in Hilbert Space Multi-Reference Coupled Cluster (HSMRCC) Theory. This is done through the use of a functional with Lagrange multipliers corresponding to HSMRCC method, as done by Helgaker, Jorgensen and Szalay. We derive explicit expressions upto third order energy derivatives. Using (2n + 1) and (2n + 2) rules, the cancellation of higher order derivatives of functional parameters that are not necessary according to these rules, is explicitly demonstated. Simplified expressions are presented. We discuss several aspects of the functional used and its potential implications.
Keywords: Energy Derivatives; Lagrange Multipliers; Constrained Variation; Hilbert Space Multi-Reference; Coupled Cluster Energy Derivatives; Lagrange Multipliers; Constrained Variation; Hilbert Space Multi-Reference; Coupled Cluster
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Export to BibTeX |
EndNote


MDPI and ACS Style

Shamasundar, K.R.; Pal, S. Higher Energy Derivatives in Hilbert Space Multi-Reference Coupled Cluster Theory : A Constrained Variational Approach. Int. J. Mol. Sci. 2002, 3, 710-732.

AMA Style

Shamasundar KR, Pal S. Higher Energy Derivatives in Hilbert Space Multi-Reference Coupled Cluster Theory : A Constrained Variational Approach. International Journal of Molecular Sciences. 2002; 3(6):710-732.

Chicago/Turabian Style

Shamasundar, K. R.; Pal, Sourav. 2002. "Higher Energy Derivatives in Hilbert Space Multi-Reference Coupled Cluster Theory : A Constrained Variational Approach." Int. J. Mol. Sci. 3, no. 6: 710-732.


Int. J. Mol. Sci. EISSN 1422-0067 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert