单分子层膜的相对电容率计算

Calculation of the Relative Permittivity of Langmuir Monolayer

采用取向序参数计算了基底表面有机单分子层膜的相对电容率(相对介电常量).计算考虑了分子固有偶极矩负电荷中心与分子在基底上的联接端不一致,以及在一定区域内电偶极子不能视为点偶极子的情况.计算结果表明:对于成份一定的稳定构型单分子层膜,其相对电容率大小除了依赖于分子密度和基底物质的相对电容率外,对分子负电荷中心离基底的距离,以及考虑电偶极子长度的分子区域大小也有不同程度的依赖.

The relative permittivity of the Langmuir monolayer on a substrate surface is calculated by the orientation order S with consideration of the length of the permanent dipoles within domain and the distance between the dipole and the substrate. It is shown that the relative permittivity of a monolayer with stable configuration not only depends on the relative permittivity of the substrate but also on the distance between the dipole and the substrate as well as the length of the permanent dipoles.