Progress in the knowledge of ‘ruby silvers’: New structural and chemical data of pyrostilpnite, Ag₃SbS₃

Abstract

The crystal structure of pyrostilpnite from the Plaka mine, Lavrion Mining District, Greece, was refined in the space group P21/c to a final R1 index of 0.0283 on the basis of 2047 reflections with Fo > 4σ(Fo) and 65 refined parameters. Unit-cell parameters of the crystal examined are a = 6.8629(6), b = 15.8800(14), c = 6.2711(5) Å, β = 117.087(2)°, V = 608.48(9) Å3 and Z = 4. Chemical data agree with the stoichiometric formula Ag3SbS3. The crystal structure reported previously was confirmed, although a higher precision of refinement was achieved. It can be described as formed by {010} slabs running along c and connected along a through relatively longer Ag–S bonds. The analysis of the atomic displacement parameters together with a refinement with higher order tensors in the expression of the structure factors revealed no hint for pyrostilpnite as an ionic conductor. A historical background of the ‘ruby silvers’ is also reported.

Electronic structure and optical properties of the Ag3SbS3 crystal: experimental and DFT studies

“…Therefore, for the Ag 3 SbS 3 crystal, the d r parameter shows a good agreement between the optimized structure and the experimental one, and the small deviation obeys the well-known tendency that LDA underestimates the crystal cell volume and GGA slightly overestimates it. 41 The obtained results indicate fine relation between the theoretical and experimental structures of the studied material. The theoretically obtained optimized x / a , y / b , and z / c relative coordinates of atoms of the Ag 3 SbS 3 crystal together with the experimental coordinates presented in ref.…”

“…The XRD study of the Ag 3 SbS 3 crystal structure, particularly on mineral samples has been performed in previous studies. 29,[40][41][42] Crystal lattices of two types are known for the pyrargyrite crystal. The crystal structure of Ag 3 SbS 3 , hR42,161 29 and Ag 3 SbS 3 , mP28,14 40 compounds can be represented as stacking of empty SbS 3 polyhedra (trigonal pyramids with stibium atoms at the vertices) as shown in Fig.…”

Tellurium-rich stibiogoldfieldite and Se-bearing dantopaite from Goldfield, Nevada, USA: new crystal chemical data

“…The shortest distances at the Ag site can be compared with those observed in linearly-coordinated Ag atoms in other minerals, e.g. ~2.45 Å in pyrargyrite (Laufek et al , 2010), 2.432 Å in pyrostilpnite (Biagioni et al , 2020) and 2.416 Å in neyite (Makovicky et al , 2001).…”