Novikov S V
A. N. Frumkin Institute of Physical Chemistry and Electrochemistry, Leninsky Prospect 31, 119071 Moscow, Russia and National Research University Higher School of Economics, Myasnitskaya Ulitsa 20, Moscow 101000, Russia.
J Chem Phys. 2015 Oct 28;143(16):164510. doi: 10.1063/1.4934648.
Far tails of the density of state (DOS) are calculated for the simple models of organic amorphous material, the model of dipolar glass and model of quadrupolar glass. It was found that in both models far tails are non-Gaussian. In the dipolar glass model, the DOS is symmetric around zero energy, while for the model of quadrupolar glass, the DOS is generally asymmetric and its asymmetry is directly related to the particular geometry of quadrupoles. Far tails of the DOS are relevant for the quasi-equilibrium transport of the charge carriers at low temperature. Asymmetry of DOS in quadrupolar glasses means a principal inequivalence of the random energy landscape for the transport of electrons and holes. Possible effect of the non-Gaussian shape of the far tails of the DOS on the temperature dependence of carrier drift mobility is discussed.
针对有机非晶材料的简单模型、偶极玻璃模型和四极玻璃模型，计算了态密度（DOS）的远尾。结果发现，在这两种模型中，远尾都是非高斯的。在偶极玻璃模型中，DOS关于零能量对称，而对于四极玻璃模型，DOS通常是不对称的，其不对称性与四极子的特定几何结构直接相关。DOS的远尾与低温下电荷载流子的准平衡输运有关。四极玻璃中DOS的不对称意味着电子和空穴输运的随机能量景观存在本质上的不等价性。讨论了DOS远尾的非高斯形状对载流子漂移迁移率温度依赖性的可能影响。
