Hiroshi Ito, Reinhold Schwalm
JES
A new palladate was synthesized at 100 kbar. Electron microprobe (EM) measurement gave the average composition as: Ca3.20±0.15Au0.54±0.03Pd4.00±0.16O7.86±0.28, suggesting Pd and Au are di- and tri-valent, respectively, in the formula of Ca4-1.5xAuxPd4O8 (x to approximately 0.54). Rietveld refinement using powder X-ray diffraction data shows its tetragonal symmetry of space group P42/mmc (No. 131), a = 5.8484(2) angstroms, c = 5.5643(2) angstroms, V = 190.32(1) angstroms3, and Z = 1. This phase is closely related to the bronze, CaPd3O4, and the CaPt2O4 phase. Structurally, Pd(II) and Au(III) ions are coordinated with nearly square-planar oxygens, while Ca atoms are located in nearly cubic oxygen environments. Au and some Ca atoms partially occupy interstitial sites in the proto-CaPt2O4-type framework. This is a typical high-pressure effect which stabilizes the first alkaline-earth-gold-palladate oxide ever reported.
Hiroshi Ito, Reinhold Schwalm
JES
Eloisa Bentivegna
Big Data 2022
S. Cohen, T.O. Sedgwick, et al.
MRS Proceedings 1983
Arvind Kumar, Jeffrey J. Welser, et al.
MRS Spring 2000