ISSN:
0020-7608
Keywords:
Computational Chemistry and Molecular Modeling
;
Atomic, Molecular and Optical Physics
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The ground-state potential curve for the beryllium dimer is calculated as a critical test case for methods based on many-body perturbation theory (MBPT) and configuration interaction (CI). In particular, the recently proposed double excitation (DE) MBPT method is compared to the standard SCF-CI method including single and double excitations from a single reference determinant. The SCF-CI method is shown to give surprisingly accurate results compared to more complete CI calculations including a larger configuration space, whereas the DE-MBPT method breaks down more or less completely, particularly for larger basis sets. The results thus demonstrate the importance of including the renormalization terms in this case. Finally, Davidson's correction and related methods lead to an even more severe breakdown than the DE-MBPT method.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/qua.560140505
