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Theoretical Chemistry Accounts

, 136:138 | Cite as

One- and multiconfigurational study of excited states of He atom in a small impenetrable cavity

  • Vladimir I. Pupyshev
  • H. E. MontgomeryJr.
Regular Article

Abstract

The system of ten low-lying electronic states of a helium atom placed in the center of an impenetrable spherical cavity of radius R c is studied for the case of small cavities. The methods for numerical and qualitative study of the atomic systems in small cavities are analyzed. The problem is studied by the finite-difference variants of the restricted SCF, the simple restricted CI and explicitly correlated Hylleraas-type approximations (for S-states). The limited applicability of the SCF approximation for excited states is demonstrated. The importance of the relatively low-lying configurations 2p 2 and corresponding states 1S, 3P and 1D is confirmed by numerical calculations and correlation diagrams.

Keywords

Helium atom Configuration interaction Confined atom Self-consistent field 

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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2017

Authors and Affiliations

  1. 1.Laboratory of Molecular Structure and Quantum Mechanics, Department of ChemistryLomonosov Moscow State UniversityMoscowRussia
  2. 2.Chemistry ProgramCentre CollegeDanvilleUSA

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