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Title: Communication: Automatic code generation enables nuclear gradient computations for fully internally contracted multireference theory

 [1]; ORCiD logo [1]
  1. Department of Chemistry, Northwestern University, 2145 Sheridan Rd., Evanston, Illinois 60208, USA
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Journal Article: Publisher's Accepted Manuscript
Journal Name:
Journal of Chemical Physics
Additional Journal Information:
Journal Volume: 142; Journal Issue: 5; Related Information: CHORUS Timestamp: 2018-02-14 09:26:19; Journal ID: ISSN 0021-9606
American Institute of Physics
Country of Publication:
United States

Citation Formats

MacLeod, Matthew K., and Shiozaki, Toru. Communication: Automatic code generation enables nuclear gradient computations for fully internally contracted multireference theory. United States: N. p., 2015. Web. doi:10.1063/1.4907717.
MacLeod, Matthew K., & Shiozaki, Toru. Communication: Automatic code generation enables nuclear gradient computations for fully internally contracted multireference theory. United States. doi:10.1063/1.4907717.
MacLeod, Matthew K., and Shiozaki, Toru. 2015. "Communication: Automatic code generation enables nuclear gradient computations for fully internally contracted multireference theory". United States. doi:10.1063/1.4907717.
title = {Communication: Automatic code generation enables nuclear gradient computations for fully internally contracted multireference theory},
author = {MacLeod, Matthew K. and Shiozaki, Toru},
abstractNote = {},
doi = {10.1063/1.4907717},
journal = {Journal of Chemical Physics},
number = 5,
volume = 142,
place = {United States},
year = 2015,
month = 2

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1063/1.4907717

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Cited by: 19works
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  • Analytical nuclear gradients for fully internally contracted complete active space second-order perturbation theory (CASPT2) are reported. This implementation has been realized by an automated code generator that can handle spin-free formulas for the CASPT2 energy and its derivatives with respect to variations of molecular orbitals and reference coefficients. The underlying complete active space self-consistent field and the so-called Z-vector equations are solved using density fitting. The implementation has been applied to the vertical and adiabatic ionization potentials of the porphin molecule to illustrate its capability.
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