Título:
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Dimerization of polyacetylene treated as a spin-Peierls distortion of the Heisenberg Hamiltonian
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Autor/a:
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García Bach, Ma. de los Ángeles; Blaise, P.; Malrieu, J. P.
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Otros autores:
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Universitat de Barcelona |
Abstract:
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Extracting a bond-length-dependent Heisenberg-like Hamiltonian from the potential-energy surfaces of the two lowest states of ethylene, it is possible to study the geometry of polyacetylene by minimization of the cohesive energy, using both variational-cluster and Rayleigh-Schrödinger perturbative expansions. The dimerization amplitude is satisfactorily reproduced. Optimizing the variational-cluster-expansion total energy with the equal-bond-length constraint, the barrier to reversal of alternation is obtained. The alternating-to-regular phase transition is treated from the Néel-state starting function and appears to be of second order. |
Materia(s):
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-Polímers -Elastòmers -Química física -Polymers -Elastomers -Physical chemistry |
Derechos:
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(c) The American Physical Society, 1992
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Tipo de documento:
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Artículo Artículo - Versión publicada |
Editor:
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The American Physical Society
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Compartir:
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