The Crystal Structures of Mn(ReO4)2·2H2O and of the Anhydrous PerrhenatesM(ReO4)2of Divalent Manganese, Cobalt, Nickel, and Zinc

✍ Scribed by A Butz; G Miehe; H Paulus; P Strauss; H Fuess

• Publisher: Elsevier Science
• Year: 1998
• Tongue: English
• Weight: 322 KB
• Volume: 138
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1998.7806

✦ Synopsis

Mn(ReO 4 ) 2 • 2H 2 O (manganese(II)-perrhenate dihydrate) is analyzed by X-ray single-crystal diffraction and TG/DTA. Space group C2/m, a ‫؍‬ 14.71(1) A s , b ‫؍‬ 5.861(6) A s , c ‫؍‬ 5.537(5) A s , ‫؍‬ 110.87(4)°, Z ‫؍‬ 2, calculated density D x ‫؍‬ 4.40 g/cm 3 . Chains of interconnected ReO 4 -tetrahedra and MnO 4 (OH 2 ) 2 -octahedra run parallel [0 1 0]. The AC-susceptibility ( eff ‫؍‬ 5.7 B ) is consistent with divalent Mn and heptavalent Re. Dehydration takes place in a single step at 150°C. Decomposition starts at 820°C. The dehydration product Mn(ReO 4 ) 2 and the isotypic anhydrous perrhenates of Co, Ni, Zn crystallize in space group P3 , Z ‫؍‬ 1; a ranges from 5.67 (Ni) to 5.86 A s (Mn), c ranges from 6.07 (Mn) to 6.17 A s (Zn), D x (g/cm 3 ) ‫؍‬ 5.11 (Mn), 5.36 (Co), 5.44 (Ni), 5.33 (Zn). The structure is topologically equivalent to that of -Zr(MoO 4 ) 2 . M 2؉ O 6 -octahedra are linked by ReO 4 -tetrahedra to form layers which are not interconnected.