2002 Molybdenum

MolybdenumI 5600 (Se4)2[Mo2O2Cl8][MCl6] (M: Zr Hf) — Tetraselenium(2+)Halometalates with Two

Different Anions. — Air-sensitive crystals of the title compounds are obtained in quantitative yield from the reactions of Se4[Mo2O2Cl8] with Se4[MCl6] (M: Zr, Hf) at 180 °C (evacuated glass tube, 5 d) and subsequent treatment in a temperature gradient (130→115 °C, 20 d for M: Zr and 160→140 °C, 5 d for M: Hf). The isotypic com-pounds crystallize in the monoclinic space group P21/C with Z = 2 and contain square-planar Se2+ cations, edge-shared [Mo2O2Cl8]2- double-octahedra, and almost regular [MCl6]2- octahedra. Magnetic measurements for (Se4)2[Mo2O2Cl8][ZrCl6] indi-cate paramagnetic behavior with only weak interactions between the paramagnetic centers. The magnetic moment of 1.7 µB is consistent with the presence of MoV in d1 configuration and supports the ionic formula. — (BECK*, J.; KELLNER, M.; KREUZINGER, M.; Z. Anorg. Allg. Chem. 628 (2002) 12, 2656-2660; Inst. Anorg. Chem., Rhein. Friedrich-Wilhelms-Univ., D-53121 Bonn, Germany; Eng.) — Schramke

05- 021