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Title: A new scheme for perturbative triples correction to (0,1) sector of Fock space multi-reference coupled cluster method: Theory, implementation, and examples

We propose a new elegant strategy to implement third order triples correction in the light of many-body perturbation theory to the Fock space multi-reference coupled cluster method for the ionization problem. The computational scaling as well as the storage requirement is of key concerns in any many-body calculations. Our proposed approach scales as N{sup 6} does not require the storage of triples amplitudes and gives superior agreement over all the previous attempts made. This approach is capable of calculating multiple roots in a single calculation in contrast to the inclusion of perturbative triples in the equation of motion variant of the coupled cluster theory, where each root needs to be computed in a state-specific way and requires both the left and right state vectors together. The performance of the newly implemented scheme is tested by applying to methylene, boron nitride (B{sub 2}N) anion, nitrogen, water, carbon monoxide, acetylene, formaldehyde, and thymine monomer, a DNA base.
Authors:
; ;  [1]
  1. Physical Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008 (India)
Publication Date:
OSTI Identifier:
22416039
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 142; Journal Issue: 4; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ACETYLENE; ANIONS; BORON NITRIDES; CARBON MONOXIDE; CORRECTIONS; DNA; EQUATIONS OF MOTION; FORMALDEHYDE; MANY-BODY PROBLEM; MONOMERS; NITROGEN; PERTURBATION THEORY; THYMINE; VISIBLE RADIATION; WATER