Non-Debye charge screening and adsorbed-ion-induced anchoring transition in a nematic liquid crystal

Anchoring transition mechanism due to substrate-adsorbed ions is studied. I t is shown that the surface field is screened by a very dense charged subsu rface layer whose thickness lambda (S) is much smaller than the Debye lengt h lambda (D). It is shown both theoretically and experimentally that critic al temperature of the transition can be controlled by bulk ion density thro ugh its relation to the density of adsorbed ions.