Premium
Partial fourth order electron propagator theory
Author(s) -
Ortiz J. V.
Publication year - 1988
Publication title -
international journal of quantum chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.484
H-Index - 105
eISSN - 1097-461X
pISSN - 0020-7608
DOI - 10.1002/qua.560340846
Subject(s) - propagator , dipole , diagonal , valence (chemistry) , order (exchange) , electron , ionization , third order , valence electron , chemistry , perturbation theory (quantum mechanics) , atomic physics , computational chemistry , physics , quantum mechanics , mathematics , ion , finance , economics , philosophy , geometry , theology
Third order diagonal self‐energies are augmented with fourth order terms that are easily determined from by‐products of a third order calculation. Comparisons are made with the outer valence approximation, a method for estimating fourth and higher order terms. The number of operations needed for all of these procedures is less than the number required for the limited two electron integral transformation. Improved one‐electron reduced density matrices are another useful by‐product of these calculations. The present methods are applied to calculating the ionization energies and dipole moments of the anions F − , OH − , NH − 2 , Cl − , SH − , PH 2 − , and CN − . The basis sets used in these calculations have been shown to be sufficiently flexible in a variety of calculations.