The New Mercury Vanadium Phosphate Hg4VO(PO4)2 Containing Hg2+2 Dumbbells: Crystal Structure and Thermal and Magnetic Properties

Single crystals of Ag2Cu2O3 were prepared by solid state reaction of Ag2O and CuO applying an oxygen pressure of 200 MPa. Crystals of Ag2Cu2O3 (I41/amd, a=589.78(6), c=1071.4(2) pm from single crystal data, Z=4, 289 unique diffractometer data, R1=0.043, wR2=0.098) are black and stable in air and moisture. The refinement of the crystal structure confirms previous results as obtained from powder data; however, the process has lead to improved precision. Electrochemical deintercalation experiments have been performed. From electrotitration curves and structural investigations on the resulting deintercalated phases we have been able to deduce an irreversible "single phase mode" deintercalation mechanism.