Mysterious charge ordering on θ-(BEDT-TTF)2RbZn(SCN) 4

Abstract

We have performed thermal studies of a charge disproportionation induced metal-insulator transition in θ-(BEDT-TTF)2RbZn(SCN) 4 system. We have detected a sharp peak in a heating process and a broad hump in a cooling process with a remarkable hysteresis. This peculiar transition could be easily suppressed by a rapid-cooling. In the successive heating process, system shows a reentrant metal-insulator-metal transition. At the transition, a drastic lattice modulation brings about this mysterious first order phase transition accompanying a notable hysteresis and the rapid-cooling effect. © 2009 IOP Publishing Ltd.