Desorption-induced first-order phase transition in a cyano-bridged compound

Abstract

The guest-host interaction is one of the promising tools to control the material state. Here, we found that a cyano-bridged compound Na0.50 Co [Fe (CN)6] 0.72 3.8 H2 O shows a first-order structural phase transition below a critical pressure Pc (150 Pa) at 300 K. Judging from suppression of the OH stretching mode in the infrared spectra, we ascribed the phase transition to desorption of the ligand waters. The phase transition accompanies a significant change of the visible absorption spectra, reflecting the strong hybridization between the Co eg state and the CN states. © 2008 American Institute of Physics.