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A self-consistent perturbative evaluation of ground state energies: application to cohesive energies of spin lattices

Mohamad Al Hajj·Jean-Paul Malrieu
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Abstract

The work presents a simple formalism which proposes an estimate of the ground state energy from a single reference function. It is based on a perturbative expansion but leads to non linear coupled equations. It can be viewed as well as a modified coupled cluster formulation. Applied to a series of spin lattices governed by model Hamiltonians the method leads to simple analytic solutions. The so-calculated cohesive energies are surprisingly accurate. Two examples illustrate its applicability to locate phase transition.

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Mohamad Al Hajj, Jean-Paul Malrieu. 2004-11-21. A self-consistent perturbative evaluation of ground state energies: application to cohesive energies of spin lattices. https://doi.org/10.1103/physrevb.70.184441

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