Theoretical and Experimental Chemistry

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

Excitation spectrum of heisenberg spin chains

  • V. O. Cheranovskii
Brief Communications


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.


Anisotropy Excitation Spectrum Molecular System Spin Chain Weak Restriction 
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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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