Effective fragment potential method in Q-CHEM: A guide for users and developers

نویسندگان

  • Debashree Ghosh
  • Dmytro Kosenkov
  • Vitalii Vanovschi
  • Joanna Flick
  • Ilya Kaliman
  • Yihan Shao
  • Andrew T. B. Gilbert
  • Anna I. Krylov
  • Lyudmila V. Slipchenko
چکیده

A detailed description of the implementation of the effective fragment potential (EFP) method in the Q-CHEM electronic structure package is presented. The Q-CHEM implementation interfaces EFP with standard quantum mechanical (QM) methods such as Hartree-Fock, density functional theory, perturbation theory, and coupled-cluster methods, as well as with methods for electronically excited and open-shell species, for example, configuration interaction, time-dependent density functional theory, and equation-of-motion coupled-cluster models. In addition to the QM/EFP functionality, a "fragment-only" feature is also available (when the system is described by effective fragments only). To aid further developments of the EFP methodology, a detailed description of the C++ classes and EFP module's workflow is presented. The EFP input structure and EFP job options are described. To assist setting up and performing EFP calculations, a collection of Perl service scripts is provided. The precomputed EFP parameters for standard fragments such as common solvents are stored in Q-CHEM's auxiliary library; they can be easily invoked, similar to specifying standard basis sets. The instructions for generating user-defined EFP parameters are given. Fragments positions can be specified by their center of mass coordinates and Euler angles. The interface with the IQMOL and WEBMO software is also described.

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عنوان ژورنال:
  • Journal of computational chemistry

دوره 34 12  شماره 

صفحات  -

تاریخ انتشار 2013