J. Phys. II France
Volume 3, Numéro 4, April 1993
Page(s) 435 - 441
DOI: 10.1051/jp2:1993101
J. Phys. II France 3 (1993) 435-441

Order-by-order expansions for intermediate Hamiltonians by the shift technique

A.V. Zaitsevskii

Laboratory of Molecular Structure and Quantum Mechanics, Chemical Department, M. Lomonossov Moscow State University, 119899 Moscow GSP, Russia

(Received 10 December 1992; accepted 16 February 1993)

The level shift technique is applied to derive rigorous order-by-order intermediate Hamiltonian QDPT expansions. The novel approach offers an insight into the relations between different intermediate Hamiltonian theories. The direct comparison with the shifted QDPT expansions for conventional effective Hamiltonian is also presented.


© Les Editions de Physique 1993