Theory for Photoinduced Ionic-Neutral Structural Phase Transition in Quasi One-Dimensional Organic Molecular Crystal TTF-CA
Theory for Photoinduced Ionic-Neutral Structural Phase Transition in Quasi One-Dimensional Organic Molecular Crystal TTF-CA
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准一维有机分子晶体TTF-CA中光致离子-中性结构相变理论
DOI：
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发表时间：
2000
期刊：
影响因子：
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通讯作者：
K. Nasu
中科院分区：
文献类型：
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作者：
P. Huai;Hang Zheng;K. Nasu
使用绝热近似值和均值近似理论，使用了准一维扩展PEIERLS-HUBBARD模型，理论上我们从有机分子链晶体TTF-CA中研究了光诱导的离子 - 中性结构相变。该模型包括强烈的链内库仑相互作用，非线性取决于TTF和CA分子之间的距离，还包括弱链间相互作用。我们将担心离子相刚好低于中性的情况，并且研究了它们的能量和电荷（自旋）分布及其能带结构。此外，我们通过经典的蒙特卡洛方法计算光吸收光谱，包括激子效应和热晶格波动。我们还研究了电荷转移（CT）激子的非线性晶格松弛，并阐明从其弗朗克 - 康登状态到宏观中性结构域的绝热路径。这个域，与CT激子分开...
Using a quasi one-dimensional extended Peierls-Hubbard model, we theoretically study the photoinduced ionic-neutral structural phase transition in an organic molecular chain crystal TTF-CA, by means of the adiabatic approximation and the mean-field theory. This model includes strong intra-chain Coulomb interactions which nonlinearly depend on the distance between TTF and CA molecules, and it also includes a weak inter-chain interaction. We will be concerned with the case that the ionic phase is just below the neutral one, and their energies and charge (spin) distribution are investigated, as well as their energy band structures. Moreover, we calculate the optical absorption spectrum by the classical Monte-Carlo method, including the exciton effect and the thermal lattice fluctuations. We also study the nonlinear lattice relaxation of a charge transfer (CT) exciton, and clarify the adiabatic path from its Franck-Condon state to a macroscopic neutral domain. This domain, being separated from the CT exciton ...