Theoretical and Experimental Chemistry

, Volume 26, Issue 1, pp 5–9 | Cite as

Use of a dynamic shift scheme for the levels of Brillouin states in the super-CI method

  • A. S. Aver'yanov
  • Yu. G. Khait


We propose a dynamic shift method for the levels of the Brillouin states, providing reliable and sufficiently rapid convergence of the iteration process in the CASSCF method with optimization of the orbitals according to the super-CI scheme. In each step of the super-CI procedure, the shift parameters are determined automatically and individually for each Brillouin state. The proposed method is simple and easy to carry out. It also guarantees that a physically incorrect solution cannot appear. The method was carried out using the CASSCF programming package; for the example of specific calculations for the1Σ+ state of the TiO molecule, we show that the method is efficient and preferred.


Programming Package Iteration Process Specific Calculation Shift Parameter Rapid Convergence 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Plenum Publishing Corporation 1990

Authors and Affiliations

  • A. S. Aver'yanov
    • 1
  • Yu. G. Khait
    • 1
  1. 1.Scientific-Industrial Association “State Institute of Applied Chemistry,”Leningrad

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