The dielectric constant of a monolayer with dielectric anisotropy on a material surface was calculated with consideration of the local field acting on polar molecules. In the calculation, a monolayer of constituent rodlike molecules with a permanent dipole moment not parallel to the molecular long axis is assumed to form an infinite two-dimensional array. It was found that at the molecule density where the maximum tilt angle is theta(A) = theta k = (root 3 - 1)/2, i.e., A/A(0) = root 3/2 (A(0) = pi l(2), where l the length of the rodlike molecule), the dielectric-anisotropic monolayer films degenerate to dielectric-isotropic films with an apparent electronic polarizability <(alpha)over bar> = (alpha(parallel to) + alpha(perpendicular to))/2, in the first-order approximation. In the small molecular area A展开▼
机译：考虑到作用在极性分子上的局部电场，计算出在材料表面具有介电各向异性的单层介电常数。在计算中，假定具有不平行于分子长轴的永久偶极矩的组成棒状分子的单层形成无限二维阵列。发现在最大倾斜角为theta（A）= theta k =（root 3-1）/ 2的分子密度下，即A / A（0）= root 3/2（A（0）= pi l（2），其中l为棒状分子的长度），介电各向异性单层薄膜退化为具有明显电子极化率<αover bar> =（α（平行于）+ alpha（垂直于））/ 2，在一阶近似中。在小分子区域A <根3A（0）/ 2中，分子变成单轴的，在分子长轴方向上具有明显的偶极矩mu cos theta（D）。由取向分布和分子的介电各向异性之间的耦合产生的附加相对介电常数的极性在平均场近似中为负，而在分子面积接近临界面积A的情况下为正。 （0）。 [参考：14]
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