Electrical conduction studies on the partially oxidised metal-atom chain compounds K2Pt(CN)4Cl0·32,2·6H2O and K2Pt(CN)4Br0·30,2·3H2O

Abstract

The a.c. and d.c. conductivities are reported for single crystals of the partially oxidised metal-atom chain compounds K₂Pt(CN)₄Cl_0·32,2·6H₂O and K₂Pt(CN)₄Br_0·30,2·3H₂O For d.c. fields of < 120 V cm^–1 the initial conductivity in the direction of the metal-atom chain is 10^–4Ω^–1 cm^–1 but this decreases with time to 10^–6Ω^–1 cm^–1. The conductivity in the direction perpendicular to the metal atom chains is 100 times lower. The a.c. conductivity is similar to those measured using d.c. potentials. The application of a d.c. field of > 120 V cm^–1 in the direction of the metal-atom chain induces an oxidation–reduction reaction which commences at the anode and spreads through the crystal to the cathode; the product of the reaction is K₂Pt(CN)₄,2H₂O in a polycrystalline form.