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arXiv · 1904.00097

autoCAS: a program for fully automated multi-configurational calculations

Christopher J. Stein·Markus Reiher
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Abstract

We present our implementation autoCAS for fully automated multi-configurational calculations, which we also make available free of charge on our webpages. The graphical user interface of autoCAS connects a general electronic structure program with a density matrix renormalization group program to carry out our recently introduced automated active space selection protocol for multi-configurational calculations [J. Chem. Theory Comput., 2016, 12, 1760]. Next to this active space selection, autoCAS carries out several steps of multi-configurational calculations so that only a minimal input is required to start them, comparable to that of a standard Kohn-Sham density functional theory calculation, so that black-box multi-configurational calculations become feasible. Furthermore, we introduce a new extension to the selection algorithm that facilitates automated selections for molecules with large valence orbital spaces consisting of several hundred orbitals.

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Christopher J. Stein, Markus Reiher. 2019-03-29. autoCAS: a program for fully automated multi-configurational calculations. https://doi.org/10.1002/jcc.25869

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