Giant infrared intensity of the Peierls mode at the neutral-ionic phase transition.
Giant infrared intensity of the Peierls mode at the neutral-ionic phase transition.
复制标题
中性离子相变时 Peierls 模式的巨大红外强度。
作者：
Luca Del Freo;A. Painelli;Z. Soos
我们提出了精确的对角化结果的中性离子相变的修改Peierls-Hubbard模型。Peierls模式的基态势能面和红外强度指向强的非线性电子-声子耦合，其影响主要由电子不稳定性的接近度而不是电子相关性决定。在铁电转变时的Peierls模的巨大红外强度与混合堆叠有机晶体的介电常数的温度依赖性有关。
We present exact diagonalization results on a modified Peierls-Hubbard model for the neutral-ionic phase transition. The ground state potential energy surface and the infrared intensity of the Peierls mode point to a strong, nonlinear electron-phonon coupling, with effects that are dominated by the proximity to the electronic instability rather than by electronic correlations. The huge infrared intensity of the Peierls mode at the ferroelectric transition is related to the temperature dependence of the dielectric constant of mixed-stack organic crystals.