THE CRYSTAL-STRUCTURES OF MN(REO4)(2)CENTER-DOT-2H(2)O AND OF THE ANHYDROUS PERRHENATES M(REO4)(2) OF DIVALENT MANGANESE, COBALT, NICKEL, AND ZINC

Mn(ReO4)(2). 2H(2)O (manganese(II)-perrhenate dihydrate) is analyzed b y X-pay single-crystal diffraction and TG/DTA. Space group C2/m, a = 1 4.76 (1) Angstrom, b = 5.861(6) Angstrom, c= 5.537(5) Angstrom, beta = 110.87(4)degrees, Z = 2, calculated density D-x = 4.40 g/cm(3). Chain s of interconnected ReO4-tetrallaedra and MnO4(OH2)(2)-octahedra run p arallel [0 1 0], The AC-susceptibility (mu(eff) = 5.7 mu(B)) is consis tent with divalent Mn and heptavalent Re. Dehydration takes place in a single step at 150 degrees C. Decomposition starts at 820 degrees C. The dehydration product Mn(ReO4)(2) and the isotypic anhydrons perrhen ates of Co, Ni, Zn crystallize in space group P (3) over bar, Z = 1; a ranges from 5.67 (Ni) to 5.86 Angstrom (Mn), c ranges from 6.07 (Mn) to 6.17 Angstrom (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 beta- Zr(MoO4)(2). M2+O6-octahedra are linked by ReO4-tetrahedra to form lay ers which are not interconnected. (C) 1998 Academic Press.