Advances in molecular quantum chemistry contained in the Q-Chem 4 program package


Yihan Shao, University of California, Berkeley
Zhengting Gan, Oak Ridge National Laboratory
Evgeny Epifanovsky, University of Southern California
Michael Wormit, Johann Wolfgang Goethe-Universität
Joerg Kussmann
Adrian Lange, Ohio State University
Andrew Behn
Jia Deng
Xintian Feng, University of Southern California
Debashree Ghosh, Council of Scientific and Industrial Research
Matthew Goldey, University of California, Berkeley
Paul R. Horn, University of California, Berkeley
Leif D. Jacobson, The Ohio State University
Ilya Kaliman, Purdue University
Rustam Z. Khaliullin, University of California, Berkeley
Tomasz Kus, University of Southern California
Arie Landau, University of Southern California
Jie Liu, Xiamen University
Emil I. Proynov, Q-Chem Inc.
Young Min Rhee, University of California, Berkeley
Ryan M. Richard, The Ohio State University
Mary A. Rohrdanz, The Ohio State University
Ryan P. Steele, Utah State University
Eric J. Sundstrom, University of California, Berkeley
H. Lee Woodcock III, University of South Florida
Paul M. Zimmerman, University of California, Berkeley
Dmitry Zuev, University of Southern California
Ben Albrecht, University of Pittsburgh
Ethan Alguire, University of Pennsylvania
Brian Austin, University of California, Berkeley
Gregory J. O. Beran, University of California, Riverside
Yves A. Bernard, University of Southern California
Eric Berquist, Q-Chem, Inc.
Kai Brandhorst, University of California, Berkeley
Ksenia B. Bravaya, University of Southern California
Shawn T. Brown, Q-Chem, Inc.
David Casanova, University of California, Berkeley
Chun-Min Chang, Q-Chem, Inc.
Yunqing Chen, The University Of Michigan
Siu Hung Chien, Q-Chem, Inc.
Kristina D. Closser, Q-Chem, Inc.
Deborah L. Crittenden, Australian National University
Michael Diedenhofen
Robert A. DiStasio Jr., University of California, Berkeley
Hainam Do, University of Nottingham
Anthony Dutoi, University of the PacificFollow

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Molecular Physics











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A summary of the technical advances that are incorporated in the fourth major release of the Q-Chem quantum chemistry program is provided, covering approximately the last seven years. These include developments in density functional theory methods and algorithms, nuclear magnetic resonance (NMR) property evaluation, coupled cluster and perturbation theories, methods for electronically excited and open-shell species, tools for treating extended environments, algorithms for walking on potential surfaces, analysis tools, energy and electron transfer modelling, parallel computing capabilities, and graphical user interfaces. In addition, a selection of example case studies that illustrate these capabilities is given. These include extensive benchmarks of the comparative accuracy of modern density functionals for bonded and non-bonded interactions, tests of attenuated second order Møller–Plesset (MP2) methods for intermolecular interactions, a variety of parallel performance benchmarks, and tests of the accuracy of implicit solvation models. Some specific chemical examples include calculations on the strongly correlated Cr2 dimer, exploring zeolite-catalysed ethane dehydrogenation, energy decomposition analysis of a charged ter-molecular complex arising from glycerol photoionisation, and natural transition orbitals for a Frenkel exciton state in a nine-unit model of a self-assembling nanotube.