Ferroelectric phase transition, ionicity condensation, and multicriticality in charge transfer organic complexes
Abstract
To elucidate a novel pressure-temperature phase diagram of the quasi-one-dimensional mixed-stack charge-transfer (CT) complex TTF-CA, we study the quasi-one-dimensional spin-1 Blume-Emery-Griffith (BEG) model. In addition to the local charge transfer energy and the inter-stack polar (dipole-dipole) interaction, we take account of the inter-stack electrostriction effect. Using the self-consistent chain-mean-field theory, where the intra-stack degrees of freedom are exactly treated by the transfer-matrix method, we reproduce the gas-liquid-solid like phase diagram corresponding to the neutral (N), paraelectric ionic (I), and ferroelectric ionic (I) phases, respectively. We also give an explanation on the experimentally observed multicritical behavior and concomitant discontinuous inter-stack lattice contraction in TTF-CA.
Keywords
Cite
@article{arxiv.cond-mat/0307731,
title = {Ferroelectric phase transition, ionicity condensation, and multicriticality in charge transfer organic complexes},
author = {Jun-ichiro Kishine and Tadeusz Luty and Kenji Yonemitsu},
journal= {arXiv preprint arXiv:cond-mat/0307731},
year = {2009}
}
Comments
6 pages, 5 figures