Title




Exact density matrix for a twoelectron model atom and approximate proposals for realistic twoelectron systems
 
Author




 
Abstract




Moshinsky introduced an exactly soluble model of a twoelectron atom consisting of two spin1/2 particles interacting via harmonic forces and moving in a harmonicoscillator potential. Here, the exact groundstate density rho(r) is related to the (also analytically known) HartreeFock density rho(HF)(r). The generalization to the offdiagonal matrix gamma(r,r(')) is then effected, this being related to the idempotent gamma(HF)(r,r('))/2. This exact information on this "model atom" prompts us to propose an approximate form of gamma(r,r(')) for the Helike ions, the H2 molecule and, in general, all twoelectron systems. gamma(r,r(')) is constructed solely from the exact rho(r) and its HartreeFock counterpart. Some detailed treatment of the twoelectron Hookean atom with spring constant k=1/4 (atomic units) is also presented. 
 
Language




English
 
Source (journal)




Physical review : A : atomic, molecular and optical physics.  Lancaster, Pa, 1990  2015
 
Publication




Lancaster, Pa
:
2003
 
ISSN




10941622
[online]
10502947
[print]
 
Volume/pages




67
:2
(2003)
, p. 16
 
Article Reference




022509
 
ISI




000181361200054
 
Medium




Eonly publicatie
 
Full text (Publisher's DOI)




 
Full text (open access)




 
