Electrochemical tunable magnetic phase transition in a high-T_c chromium cyanide thin film

Molecular-based ferrimagnetic thin films with high critical temperatures (T_c) composed of mixed-valence chromium cyanides were synthesized by means of a simple electrochemical route. The highest T_c was 270 K, obtained for Cr_2.12(CN)₆. The T_c values were easily controlled by changing the preparation conditions. Moreover, a reversible shift of T_c could be electrochemically induced. As a result of such electrochemical control, these cyanides can be switched reversibly back and forth between ferrimagnetism and paramagnetism. These magnets thus represent materials in which magnetic properties are combined with electrical functions.