hide
Free keywords:
layer compounds; silver nickelates; intercalation; staging; subvalency
Abstract:
Ag3Ni2O4 was obtained as single crystals from a mixture of 2H-AgNiO2 and Ag2O in oxygen high-pressure autoclaves (P6(3)/mmc (no. 194), a = 2.9331(6), c = 28.313(9) angstrom, Z = 2). It may be regarded as a stage-2 intercalation compound of the host 2H-AgNiO2 and is the first staging compound constituted of alternating subvalent infinity(2) Ag-2(+) and Ag+ sheets, inserted between NiO2- slabs. From a structural point of view, Ag3Ni2O4 represents an intermediate between AgNiO2 and the recently reported Ag2NiO2. The electronic structures of 2H-AgNiO2 and Ag3Ni2O4 have been investigated based on DFT band structure calculations. The high-temperature characteristics of the starting material 2H-AgNiO2 were investigated. The inverse magnetic susceptibility, electrical resistivity and differential scanning calorimetry (DSC) show a phase transition in the temperature range of T = 320-365 K. (c) 2006 Elsevier Inc. All rights reserved.
