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Theoretical and Experimental Chemistry

, Volume 24, Issue 2, pp 198–201 | Cite as

Excitation spectrum of heisenberg spin chains

  • V. O. Cheranovskii
Brief Communications

Abstract

In the framework of the Heisenberg model of interacting spins we prove the existence of a continuum of zero-activation excitations in the spectrum of alternant spin chains with a non-singular ground state. It is shown that for certain weak restrictions on the spin moment M, the excitations of the lower part of the spectrum with given M are continuous. The results are extended to the case of spin anisotropy, which effectively appears in the spin Hamiltonian method with the use of the Hartree-Fock approximation. For one-dimensional molecular systems described by the Parizer-Papp-Pople (PPP) Hamiltonian, the existence of a continuum of zero-activation excitations is established, provided that the ground state of the system is nondegenerate and nonsingular.

Keywords

Anisotropy Excitation Spectrum Molecular System Spin Chain Weak Restriction 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Publishing Corporation 1988

Authors and Affiliations

  • V. O. Cheranovskii
    • 1
  1. 1.Kharleov UniversityUSSR

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