Perturbation calculation of molecular correlation energy using Gaussian-type geminals. Second- and third-order pair energy of H2

1999 ◽  
Vol 67 (9) ◽  
pp. 4298 ◽  
Author(s):  
Ludwik Adamowicz
Keyword(s):  
Correlation Energy ◽  
Perturbation Calculation ◽  
Third Order ◽  
Gaussian Type ◽  
Molecular Correlation ◽  
Pair Energy

Atomic and molecular correlation energies with explicitly correlated Gaussian geminals. II. Perturbation treatment through third order for He, Be, H2, and LiH

1983 ◽  
Vol 79 (11) ◽  
pp. 5543-5552 ◽  
Author(s):  
Krzysztof Szalewicz ◽  
Bogumil/ Jeziorski ◽  
Hendrik J. Monkhorst ◽  
John G. Zabolitzky
Keyword(s):  
Third Order ◽  
Molecular Correlation ◽  
Explicitly Correlated

A perturbation calculation of properties of the 2 pπ state of HeH 2+

1957 ◽  
Vol 240 (1221) ◽  
pp. 274-283 ◽  
Keyword(s):  
Dipole Moment ◽  
Total Energy ◽  
Second Order ◽  
Wave Functions ◽  
Quadrupole Moments ◽  
Perturbation Calculation ◽  
Third Order ◽  
The Third ◽  
Fifth Order ◽  
Kinetic And Potential Energies

A perturbation calculation, valid in the limit of large separations, of various properties of the 2 pπ state of HeH 2+ is carried out. The total energy and the kinetic and potential energies are calculated to the fifth order, the dipole moment to the third order and the quadrupole moments to the second order and the results compared with those obtained using exact and variationally determined two-centre wave functions. Some results are also given for the 2 pπ u and 3 dπ g states of H + 2 and the influence of nuclear symmetry at large separations is briefly discussed.

PERTURBATION THEORY OF THE PERIODIC ANDERSON LATTICE AND SUPERCONDUCTIVITY

1988 ◽  
Vol 02 (05) ◽  
pp. 681-687
Author(s):  
W. Geertsma
Keyword(s):  
Magnetic Field ◽  
Perturbation Theory ◽  
Fermi Level ◽  
Fourth Order ◽  
Ground State ◽  
Kondo Effect ◽  
Interparticle Interaction ◽  
Perturbation Calculation ◽  
Interparticle Interactions ◽  
Pair Energy

In this paper I develop a perturbation calculation of the second and fourth order interparticle interaction in band states, based on the Periodic Anderson Lattice. I show that 4th order interparticle interactions giving rise to the wellknown Kondo effect vanish in the superconducting ground state. This term survives in the presence of a magnetic field. Pair excitations can only give rise to an appreciable attractive contribution when the d states are less than half filled and the pair energy is near the Fermi level. The only important attractive interaction comes from the normal fourth order terms.

Sign in / Sign up

Export Citation Format

Share Document