Crystal structure of Suzukiite from the Mogurazawa Mine, Gumma Prefecture, Japan

Abstract

The crystal structure of suzukiite from the Mogurazawa mine, Gumma Prefecture, Japan is orthorhombic, space group Cmcm, a = 5.3546(16), b = 15.249(5), c = 7.094(2) Å, Z = 2.  The EPMA analysies gave an empirical formula; (Ba_0.977Sr_0.027)_{S 1.004}V_1.013Si_1.984O₇.  The refinement with single-crystal XRD data set measured on a CCD-diffractometer employing Mo Ka radiation converged into R = 0.0207 for 1508 reflections [I>2s(I)].  The refinement suggested the space group Cmcm for suzukiite.  The b parameter of suzukiite is larger than that of haradaite.  The crystal structure of suzukiite is isomorphous with that of haradaite, and consists of (Ba,Sr)O₁₁-polyhedra, SiO₄-tetrahedra,  VO₅-square pyramid.