NovelAb InitioCorrelated Calculations for an Infinite Chain of Hydrogen Atoms

Abstract

A novel cluster-expanded ab initio effective or model Hamiltonian is described and illustrated for a linear chain of hydrogen atoms. The method relies on expanding the model Hamiltonian in a sum of irreducible cluster interaction operators. A hierarchy of increasingly accurate ab initio Heisenberg spin Hamiltonians duplicate low eigenvalues of the more complete Schrödinger Hamiltonian. Finally these Heisenberg models are treated to obtain the ground-state energy and magnetic susceptibility of the infinite chain.