H. Borrmann et al., MANGANESE(II) HEXAFLUOROARSENATE - UNUSUALLY HIGH COORDINATION OF MANGANESE(II) IN A FLUORINE ENVIRONMENT, Inorganic chemistry, 36(5), 1997, pp. 880-882
Mn(AsF6)(2) was prepared from MnF2 and AsF5 in anhydrous hydrogen fluo
ride (aHF), and single crystals were grown from the respective solutio
n. The compound crystallizes in the tetragonal space group <I(4)over b
ar 2d> with a = 750.76(2) pm, c = 1544.44(5) pm, and Z = 4 at 293 K. D
ue to combined sharing of edges and apexes with AsF6 octahedra, coordi
nation number 8 (Mn-F4 x 213.0(2) pm and 4 x 241.9(3) pm) is observed
for the first time with Mn(II) and fluorine ligands. A second crystall
ine modification is formed at about 243 K. From susceptibility measure
ments a magnetic moment of 5.42 mu(B) is derived, but no magnetic orde
ring is observed above 4 K.