In:
The Journal of Chemical Physics, AIP Publishing, Vol. 110, No. 13 ( 1999-04-01), p. 6135-6142
Abstract:
The recently developed concept of a correlation entropy, S, as a quantitative measure of the correlation strength present in a correlated quantum many-body state is applied to the ground states of the He isoelectronic series He(Z) with varying nuclear charge Z and of the Hooke’s law model HLM(ω) with varying oscillator frequency ω. S is constructed from the natural orbital occupation numbers. It vanishes for weak correlation (large coupling constants Z or ω), and increases monotonically with decreasing Z or ω (strengthening correlation). A reduced correlation energy per particle Δecorr and a dimensionless ratio ε=|Ecorr/E| are introduced which vanish asymptotically in the weak correlation limit in contrast to Ecorr and ecorr=Ecorr/N. These two intensive quantities, Δecorr and ε, are compared with s=S/N. For both model systems, dΔecorr/ds⩾0 and dε/ds⩾0 (which modifies Collins’ conjecture that |Ecorr|∼S).
Type of Medium:
Online Resource
ISSN:
0021-9606
,
1089-7690
Language:
English
Publisher:
AIP Publishing
Publication Date:
1999
detail.hit.zdb_id:
3113-6
detail.hit.zdb_id:
1473050-9