Addition by subtraction in coupled cluster theory. II. Equation-of-motion coupled cluster method for excited, ionized, and electron-attached states based on the nCC ground state wave function

2007 ◽  
Vol 127 (2) ◽  
pp. 024106 ◽  
Author(s):  
Monika Musiał ◽  
Rodney J. Bartlett
Keyword(s):  
Wave Function ◽  
Ground State ◽  
Equation Of Motion ◽  
Ground State Wave Function ◽  
Cluster Method ◽  
Coupled Cluster ◽  
Coupled Cluster Method ◽  
Coupled Cluster Theory ◽  
Cluster Theory ◽  
State Wave

Multireference State-Specific Coupled-Cluster Theory and Multiconfigurationality Index. BH Dissociation

2005 ◽  
Vol 70 (7) ◽  
pp. 1017-1033 ◽  
Author(s):  
Vladimir V. Ivanov ◽  
Ludwik Adamowicz ◽  
Dmitry I. Lyakh
Keyword(s):  
Wave Function ◽  
Numerical Results ◽  
Cluster Method ◽  
Coupled Cluster ◽  
Coupled Cluster Method ◽  
Coupled Cluster Theory ◽  
Cluster Theory ◽  
Computer Aided

Multiconfigurationality index calculated for the coupled-cluster wave function based on an algorithm developed using a computer-aided generation approach is applied to analyze the multireference state-specific coupled-cluster method with the CAS reference (i.e. the so called the CAS(n,m)CCSD approach). The numerical results concern dissociation of the BH molecule where at larger displacement from the equilibrium significant quasi-degeneracy arises. The analysis shows that the CAS(n,m)CCSD approach performs very well in such a situation.

A Multi-Layer Approach to the Equation of Motion Coupled-Cluster Method for the Electron Affinity

2020 ◽  
Author(s):  
Soumi Haldar ◽  
Achintya Kumar Dutta
Keyword(s):  
Electron Affinity ◽  
Electron Attachment ◽  
Equation Of Motion ◽  
Cluster Method ◽  
Coupled Cluster ◽  
Coupled Cluster Method ◽  
Large Molecules ◽  
Layer Method ◽  
Speed Up ◽  
Attachment Process

We have presented a multi-layer implementation of the equation of motion coupled-cluster method for the electron affinity, based on local and pair natural orbitals. The method gives consistent accuracy for both localized and delocalized anionic states. It results in many fold speedup in computational timing as compared to the canonical and DLPNO based implementation of the EA-EOM-CCSD method. We have also developed an explicit fragment-based approach which can lead to even higher speed-up with little loss in accuracy. The multi-layer method can be used to treat the environmental effect of both bonded and non-bonded nature on the electron attachment process in large molecules.<br>

scholarly journals Electronically Excited States in Solution via a Smooth Dielectric Model Combined with Equation-of-Motion Coupled Cluster Theory

2017 ◽  
Vol 13 (11) ◽  
pp. 5572-5581 ◽  
Author(s):  
J. Coleman Howard ◽  
James C. Womack ◽  
Jacek Dziedzic ◽  
Chris-Kriton Skylaris ◽  
Benjamin P. Pritchard ◽  
...  
Keyword(s):  
Excited States ◽  
Equation Of Motion ◽  
Coupled Cluster ◽  
Electronically Excited States ◽  
Coupled Cluster Theory ◽  
Cluster Theory ◽  
Dielectric Model ◽  
Electronically Excited
Sign in / Sign up

Export Citation Format

Share Document