On Ag2SnO3, the first silver stannate

For the first time, crystals of red Ag2SnO3 have been obtained by solid state reaction of freshly prepared K2Sn(OH)(6) and Ag2O at 430 degrees C while applying an oxygen pressure of 350 bar. Ag2SnO3 shows a one dimensional incommensurate superstructure with a' = 33.1 Angstrom. Here we report on the basic structure of Ag2SnO3. According to the results of X-ray crystal structure determination the basic structure of Ag2SnO3 may be described in P6(3)22 (a = 5.6230(4) Angstrom, c = 12.6694(14) Angstrom, Z = 4, 968 independent reflections, R1 = 5.6%, wR2 = 12.5%). Within the layered 'SnO3' partial structure two third of the octahedral voids are occupied by tin. Those SnO3 layers are connected to each other by almost linearly coordinated silver atoms. Additionally, silver occupies the free octahedral voids within the SnO3 sheets. As expressed by the formula Ag[Ag1/3Sn2/3]O-2 the structure may be described as a super structure of Delafossite CuFeO2.