Constrained variational response to fock-space multi-reference coupled-cluster theory: formulation for excited-state electronic structure calculations and some pilot applications
Title | Constrained variational response to fock-space multi-reference coupled-cluster theory: formulation for excited-state electronic structure calculations and some pilot applications |
Publication Type | Conference Paper |
Year of Publication | 2007 |
Authors | Manohar, PUday, Pal, S |
Editor | Maroulis, G, Simos, TE |
Conference Name | Computational Methods in Science and Engineering Vol 1: Theory and Computation: Old Problems and New Challenges |
Date Published | SEP |
Publisher | European Soc Computat Methods Sci & Engn; Minist Natl Educ & Religious Affairs; E4 Comp Engn |
Conference Location | 2 Huntington Quadrangle, Ste 1no1, Melville, NY 11747-4501 USA |
ISBN Number | 978-0-7354-0477-9 |
Keywords | CVA, Dipole moment, excited states, FSMRCC, polarizability |
Abstract | Fock-space (FS) multi-reference (MR) coupled-cluster (CC) method has emerged as compact tool to account for electronic structure of open-shell systems and molecules in low-lying excited states. Development of linear response (LR) has been one of the challenging problems in FSMRCC due to multiple-root nature of effective Hamiltonian. The recently developed constrained variational approach (CVA) has opened up a promising tool for efficient evaluation of analytic response properties. In this article, we present formulation of the method for excited state calculations. We discuss the decoupling of equations as a result of spin-adaptation and present some preliminary results for analytical dipole moments and polarizabilities of some molecules in low-lying triplet excited states. |