Characterization of Monomeric Green and Polymeric Orange Forms of a Schiff Base-Oxovanadium(IV) Complex and Interconversion between These Species

抄録

{N, N'-Disalicylidene-(R, R)-1, 2-Biphenyl-1, 2-ethanediamine}oxovanadium(IV) crystallized in two different forms, green (from chlorinated solvents) and orange (from acetonitrile). X-ray structure analyses revealed that the green form contains mononuclear square pyramidal molecules of the complex, while the orange form has a polynuclear linear chain structure. The green crystals turn orange when heated at 120°C for a few minutes. The orange crystals turn green when exposed to chloroform vapor, and the green crystals turn orange when exposed to acetonitrile vapor. The orange complex shows piezochromism (mechanochromism); its color changes to green on grinding.