介质表面颗粒膜介电常数分析

Analysis of dielectric constant on a material surface for granular film

假设材料表面极性棒状分子为取向分布,采用取向序参数,考虑局域场对有极分子、固有偶极矩的作用及基底材料表面和分子之间相互作用能,计算了材料表面颗粒膜的介电常数。计算结果表明:颗粒膜的介电常数依赖于基底材料相对介电常数和棒状分子之间的距离;在分子面积和分子临界面积接近的范围内,分子和材料表面之间的相互作用能使之成为单一的贡献。反之,分子面积与分子临界面积相差较大时,局域场的相互作用是主要的贡献。

On the hypothesis that polar rod-like molecule is orientation distribution, dielectric constant of granular film on material surface was calculated by using orientation order parameters and considering the effect of local field on polar molecules with permanent dipole moment and interaction energy betweenmolecules and material surface. The results show that dielectric constant of granular film depends on relative dielectric constant of substrate material and distance between molecules. It is aslo found that interaction energy between molecules and material surface is the only influencing factor if molecule area is close to critical area. However, interaction of local fields becomes a major influencing factor if there is great difference between molecular area and critical area.