Evaluating the interaction energy between charged dielectric spheres in close contact is difficult because interfacial charge polarization becomes increasingly stronger as separation decreases. The limit of high dielectric permittivity is amenable to theoretical treatment because the particles become equipotential upon close contact. For particles with low permittivity, the constitutive equation for the induced surface charges demanded by the boundary conditions is derived in this work, based on which the contact energy of symmetric cases is evaluated. The known result for conducting spheres is recovered as a limiting case.

中文翻译：

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紧密接触的两个带电电介质球的极化能量

评估紧密接触的带电介电球之间的相互作用能非常困难，因为随着间距的减小，界面电荷极化会变得越来越强。高介电常数的限制适合于理论处理，因为颗粒在紧密接触时变为等电位。对于低介电常数的粒子，在这项工作中导出了边界条件所要求的感应表面电荷的本构方程，在此基础上评估了对称情况下的接触能。导电球的已知结果作为极限情况被恢复。