Mechanochromic properties in a mononuclear Cu(<scp>i</scp>) complex without cuprophilic interactions

Abstract

Two polymorphs of Cu[(3,4-bis(diphenylphosphino)thiophene)(bis(pyrazol-1-yl)borohydrate)] (1) were isolated. The blue luminescent crystals have evident mechanochromic luminescent (MCL) properties. Based on photophysical and structural analysis, the pore structure in the blue crystals is considered to be the main reason for the MCL properties.