Fermion-propagator calculations of excitations in polyenes with the use of a Heisenberg (XYZ) Hamiltonian. II. Applications to large systems

Vladimiro Mujica, Nestor Correia, Osvaldo Goscinski

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

A previously developed formalism for calculating excitation energies in polyenes using an effective-spin Hamiltonian is applied to large systems. The method involves only diagonalization of N×N matrices (N being the number of sites). A description of the excitation process in terms of local spin flippings is given and values of the triplet and doublet exciton gap for finite polyenes can be estimated. When applied to deformed chains with odd N, midgap states appear. Introduction of electronic correlation renders local ground-state spin densities which are in qualitative agreement with electron-nuclear double-resonance measurements. Excited-state spin densities are also discussed in some cases.

Original languageEnglish
Pages (from-to)4186-4191
Number of pages6
JournalPhysical Review B
Volume32
Issue number6
DOIs
Publication statusPublished - 1985

Fingerprint

Polyenes
Hamiltonians
Fermions
fermions
propagation
Excitation energy
Excited states
Excitons
Ground state
excitation
Electrons
excitons
formalism
ground state
matrices
electronics
electrons
LDS 751
energy

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Fermion-propagator calculations of excitations in polyenes with the use of a Heisenberg (XYZ) Hamiltonian. II. Applications to large systems. / Mujica, Vladimiro; Correia, Nestor; Goscinski, Osvaldo.

In: Physical Review B, Vol. 32, No. 6, 1985, p. 4186-4191.

Research output: Contribution to journalArticle

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