Approximating electronically excited states with equation-of-motion linear coupled-cluster theory

Journal Article · Wed Oct 28 04:00:00 EDT 2015 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.4934232· OSTI ID:22493142

Rishi, Varun; Perera, Ajith ^[1]; Bartlett, Rodney J. ^[1]

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1. Quantum Theory Project, University of Florida, Gainesville, Florida 32611 (United States)

A new perturbative approach to canonical equation-of-motion coupled-cluster theory is presented using coupled-cluster perturbation theory. A second-order Møller-Plesset partitioning of the Hamiltonian is used to obtain the well known equation-of-motion many-body perturbation theory equations and two new equation-of-motion methods based on the linear coupled-cluster doubles and linear coupled-cluster singles and doubles wavefunctions. These new methods are benchmarked against very accurate theoretical and experimental spectra from 25 small organic molecules. It is found that the proposed methods have excellent agreement with canonical equation-of-motion coupled-cluster singles and doubles state for state orderings and relative excited state energies as well as acceptable quantitative agreement for absolute excitation energies compared with the best estimate theory and experimental spectra.

• OSTI ID: 22493142
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 16 Vol. 143; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
97 MATHEMATICS AND COMPUTING
APPROXIMATIONS
COMPARATIVE EVALUATIONS
EQUATIONS OF MOTION
EXCITATION
EXCITED STATES
HAMILTONIANS
MANY-BODY PROBLEM
MOLECULES
PERTURBATION THEORY
SPECTRA
WAVE FUNCTIONS