A crystal structure determination of (selenian) kobellite from the Boliden Mine, Sweden

Abstract

Selenian kobellite is orthorhombic, Pnnm, with unit cell a = 22.6686(6), b = 34.2577(7), c = 4.04091(8)Å. The crystal structure was refined using 3259 unique intensity data with I ≤ 4 σ(I) out of a total of 30469 independent reflections measured with a single crystal diffractometer. The determined structural arrangement differs in minor ways from that reported by Miehe (1971). Selenian kobellite contains only about 1.4 -1.6 Se atoms out of a total of 17.5 (S+Se) anions per asymmetric formula unit. As such, and for the present, it continues to be best described as selenian kobellite, rather than the proposed (but not accepted), new mineral name, selenokobellite, suggested by Ödman in 1942. © ..