13596-35-5Relevant articles and documents
Woolf, Alfred A.
, p. 151 - 160 (1978)
Structure relationships between tetraselenium(2+) hexachlorometalates: Synthesis and crystal structure of Se4[ReCl6] and the solid state phase transition of Se4[MCl6](M = Zr, Hf)
Beck, Johannes,Desgroseilliers, Antje,Mller-Buschbaum, Klaus,Schlitt, Klaus-Jrgen
, p. 1145 - 1151 (2008/10/08)
The reaction of Se, SECl4, and ReCl4 in a closed, evacuated glass ampoule at 485 K yields dark-red moisture sensitive crystals of Se4[ReCl6] (orthorhombic, Pccn, a = 1091.5(1), b = 1057.2(1), c = 1015.0(1)pm). The crystal structure consists of almost square-planar Se42+ cations and slightly distorted octahedral [ReCl6]2- anions. Se4[ReCl6] is paramagnetic with a moment of 3.54 μB/Re according to a d3 configuration and Re(IV). The magnetic moment obeys the Curie-Weiss law with a Weiss constant of -33 K. The already known compounds Se4[ZrCl6] and Se4[HfCl6] crystallize in a closely related structure with tetragonal symmetry (space group P42/ncm). Both undergo a phase transition in the solid state into an orthorhombic low temperature form, which is isotypic to Se4[ReCl6]. The phase transition was monitored by single crystal and powder diffraction, the transition temperature was determined to 193(1) K for Se4[ZrCl6]. The changes of the lattice constants with temperature imply a displacive transition of mainly second order which is allowed by the translationsgleiche supergroup-subgroup relation of index 2 between the space groups. No phase transition into a tetragonal high-temperature form could be observed for the orthorhombic Se4[ReCl6].
On tetrachlorophosphonium chlorometallates of rhenium and molybdenum: Syntheses, crystal structures, and magnetism of [PCl4]2[Re2Cl10] and [PCl4]3[ReCl6]2, and the magnetic properties of [PCl4]2[Mo2Cl10]
Beck,Mueller-Buschbaum,Wolf
, p. 975 - 981 (2008/10/08)
MoCl4, ReCl4, and ReCl5 react with PCl5 in sealed glass ampoules at temperatures between 220° and 320° to [PCl4]2[Mo2Cl10] (1) [PCl4]2[Re2Cl10] (2), and [PCL4]3[ReCl6]2 (3). 2 crystallizes isotypically to the previously reported 1 and the respective titanium and tin containing analogues. The structure (triclinic, P1 Z = 1, a = 897.3(2), b = 946.0(2), c = 687.13(9) pm, α = 95.59(2)°, β = 95.80(2)°, γ = 101.07(2)°, V = 565.4(2) 106 pm3) is built of tetrahedral [PCl4]+ and edge sharing double octahedral [Re2Cl10]2- ions and can be derived from a hexagonal closest packing of Cl- ions with tetrahedral and octahedral holes partially filled by P(V) and Re(IV), respectively. 3 crystallizes isotypically to [PCL4]3[PCl6][MCl6] (M = Ti, Sn) (tetragonal, P 42/mbc, Z = 4, a = 1496.2(1), c = 1363.2(2) pm). Because no evidence was found for the presence of [PCl6]- ions, Re in 3 has to be of mixed valency with ReIV and ReV sharing the same crystallographic site. The structure can be derived from a cubic closest packing or alternatively from an only sparsely distorted body centered cubic arrangement of Cl- ions which is rarely found for anion arrays. The tetrahedral and octahedral holes are partially filled by PV and MIV/V, respectively. Magnetic measurements show all three compounds to be paramagnetic and confirm the oxidation state IV for Mo and Re in 1 and 2 and the mixed valence (IV/V) for Re in 3.
