Photo-EPR studies of electron and hole trapping by [Fe(CN)₆]^4- complexes in silver chloride

Abstract

[Fe(CN)₆]^4- was incorporated into silver chloride powders precipitated from aqueous solution with all six cyanide ligands intact. The most notable feature of this dopant was its amphoteric behavior, acting as either a deep hole trap or a shallow electron trap. The filled t_2g orbital manifold of this complex lies below the Fermi level, which places the vacant e_g levels well above the conduction band minimum. The trapping behavior of [Fe(CN)₆]^4- was determined by whether or not it was closely associated with a charge-compensating silver ion vacancy.

Key Words:

• iron hexacyanide
• silver chloride
• hole-trap
• EPR
• vacancy
• dopant.