Crystal structure and XANES investigation of petzite, Ag3AuTe2.

Petzite, Ag3AuTe2, crystallizes in the space group I4132, which is a Sohncke type of space group where chiral crystal structures can occur. The structure refinement of petzite reported long ago [Frueh (1959). Am. Mineral.44, 693–701] did not provide any information about the absolute structure. A new single‐crystal X‐ray diffraction refinement has now been performed on a sample from Lake View Mine, Golden Mile, Kalgoorlie, Australia, which has resulted in a reliable absolute structure [a Flack parameter of 0.05 (3)], although this corresponds to the opposite enantiomorph reported previously. The minimum Te–Te distance is 3.767 (3) Å, slightly shorter than the van der Waals bonding distance, which suggests a weak interaction between the two chalcogens. XANES spectra near the Au and Te LIII edges suggest that the chemical‐bonding character of Au in petzite is more metallic than in other gold minerals. A single‐crystal X‐ray diffraction and XANES investigation of the mineral petzite is reported. [ABSTRACT FROM AUTHOR]