Behaviour of NTE material Ag3[Co(CN)6] under pressure

Abstract

Recent discovery of colossal negative thermal expansion (NTE) behaviour in Silver Hexacyanocobaltate Ag3[Co(CN)6] has triggered interest among researchers to understand the basic mechanism causing such an unusual behaviour. This report presents our results on the behaviour of Ag 3[Co(CN)6] using in-situ high pressure Raman and FTIR spectroscopy. The reported trigonal-monoclinic phase transition occurring in this compound is observed at 0.2 GPa. Upon increasing the pressure further, Ag3[Co(CN)6] becomes irreversibly amorphous above 13 GPa.