13520-78-0Relevant articles and documents
Gibson, Vernon C.,Kee, Terence P.,Shaw, Alan
, p. 2293 - 2298 (1990)
Oleum and sulfuric acid as reaction media: Structural features and thermal behavior of RE2[W2O3(SO4) 6] (RE = Sm-Gd, Ho), RE2Nb2O 2(SO4)3[H(SO4)2] 2 (RE = Y, Ce-Nd, Sm-Er)
Betke, Ulf,Wickleder, Mathias S.
, p. 4400 - 4413 (2011)
The first examples of ternary sulfates containing refractory metals and trivalent ions of the rare-earth group and bismuth were prepared by solvothermal synthesis from H2SO4/SO3 mixtures. The tungsten compounds RE2[W2O3(SO 4)6] (RE = Sm-Gd, Ho) were obtained by the reaction of WOCl4 and RE2O3 in oleum (25 % SO3). They crystallize in the monoclinic space group C2/c and contain the unique [W2O3(SO4)6]6- anion. Thermal decomposition leads to the oxides RE2O(WO4) 2. Tetragonal rare-earth-niobium sulfates of the type RE 2Nb2O2(SO4)3[H(SO 4)2]2 (RE = Y, Ce-Nd, Sm-Er) (space group P421m) were synthesised from NbCl5 and RE 2O3 in 100 % H2SO4. They contain [O3SO...H...OSO3]3- ions featuring a strong hydrogen bond and form a polymeric structure with niobium in an octahedral coordination and the rare-earth ion is surrounded by eight [SO 4] tetrahedra in the form of a square antiprism. The decomposition temperature of RE2Nb2O2(SO4) 3[H(SO4)2]2 depends on the size of the respective rare-earth ion with a maximum in thermal stability found for RE = Sm-Gd (≈550 °C). The reaction of NbCl5 and Sm(NO 3)3·6H2O in oleum (25 % SO3) yielded Sm2Nb2O2(SO4) 5(S2O7), which is a possible intermediate of the thermal decomposition of Sm2Nb2O2(SO 4)3[H(SO4)2]2. It crystallizes in the monoclinic space group I2/a and contains 2 ∞[NbO(SO4)2/2(SO4) 3/3] layers connected by 2∞[Sm(SO 4)2/4(S2O7)2/4] units to a polymeric structure. Reaction of NbCl5 with (BiO) 2CO3 or Eu2O3 in 95 % H 2SO4 yielded M2Nb4O 5(SO4)8 (M = Bi, Eu, monoclinic, space group C2/c). These compounds contain the unprecedented [M2Nb 4O5]16+ cluster cation and decompose into MNbO4 and Nb2O5 on heating. Copyright
Sulfates of the refractory metals: Crystal structure and thermal behavior of Nb2O2(SO4)3, MoO 2(SO4),WO(SO4)2, and two modifications of Re2O5(SO4)2
Betke, Ulf,Wickleder, Mathias S.
, p. 858 - 872 (2011)
The sulfates Nb2O2(SO4)3, MoO2(SO4),WO(SO4)2, and two modifications of Re2O5(SO4)2 have been synthesized by the solvothermal reaction of NbCl5, WOCl 5,Re2O7(H2O)2, and MoO3 with sulfuric acid/SO3 mixtures at temperatures between 200 and 300 °C. Besides the X-ray crystal structure determination of all compounds, the thermal behavior was investigated using thermogravimetric studies. WO(SO 4)2 (monoclinic, P21/n, a = 7.453(1) A, b = 11.8232(8) A, c=7.881 (1) A, β = 107.92(2)°, V = 660.7(1) A3, Z =4) and both modifications of Re2O 5(SO4)2 (I: orthorhombic, Pba2, a = 9.649(1) A, b=8.4260(8)A, c = 5.9075(7)A, V = 480.27(9) A3, Z = 2; II: orthorhombic, Pbcm, a = 7.1544(3) A, b = 7.1619(3) A, c =16.8551 (7) A, V =863.64(6) A3, Z =4) are the first structurally characterized examples of tungsten and rhenium oxide sulfates. Their crystal structure contains layers of sulfate connected [W=O] moieties or [Re2O5] units, respectively. The cohesion between layers is realized through weak M-O contacts (343-380 pm).Nb2O2(SO4)3 (orthorhombic, Pna21, a = 9.9589(7) A, b = 11.7983(7) A, c = 8.6065(5) A, V =1011.3(1) A3, Z =4) represents a new sulfate-richer niobium oxide sulfate. The crystal structure contains a three-dimensional network of sulfate connected [Nb=O] moieties. In MoO 2(SO4)(monoclinic, 12/a, a = 8.5922(6) A, b =12.2951 (6) A, c = 25.671 (2) A β = 94.567(9)°, V = 2703.4(3) A3, Z =24)[MoO2] units are connected through sulfate ions to a three-dimensional network, which is pervaded by channels along [100] accommodating the terminal oxide ligands. In all compounds except WO(SO 4)2,the metal ions are octahedrally coordinated by monodentate sulfate ions and oxide ligands forming short M=O bonds. In WO(SO4)2, the oxide ligand and two monodentate and two bidentate sulfate ions build a pentagonal bipyramid around W. The thermal stability of the sulfates decreases in the order Nb > Mo > W > Re; the residues formed during the decomposition are the corresponding oxides.
Complexes of WOCl4 and WSCl4 with neutral N- and O-donor ligands: Synthesis, spectroscopy and structures
Greenacre, Victoria K.,Hector, Andrew L.,Levason, William,Reid, Gillian,Smith, Danielle E.,Sutcliffe, Laura
, p. 14 - 19 (2019/02/10)
The complexes [WOCl4(L)] and [WSCl4(L)] (L = OPPh3, OPMe3, pyridine, 2,2′-bipyridyl), [{WOCl4}2(μ-L-L)] and [{WSCl4}2(μ-L-L)] (L-L = Ph2P(O)(CH2)nP(O)Ph2 (n = 1, 2)) have been prepared from WOCl4 or WSCl4 and the ligands in anhydrous CH2Cl2 solution, and characterised by microanalysis, IR and NMR (1H, 31P{1H}) spectroscopy. X-Ray crystal structures are reported for [WOCl4(OPPh3)], [{WOCl4}2(μ-Ph2P(O)(CH2)P(O)Ph2)] and [{WSCl4}2(μ-Ph2P(O)(CH2)2P(O)Ph2)]. All, except those of 2,2′-bipyridyl, are six-coordinate with the neutral donor trans to W[dbnd]O or W[dbnd]S. Spectroscopic data suggest that the [WOCl4(2,2′-bipy)] and [WSCl4(2,2′-bipy)] are seven-coordinate. Comparison of the structural and spectroscopic data for the two series of complexes indicate little difference in Lewis acidity between the two tungsten(VI) moieties. Decomposition of [WOCl4(OPMe3)] in solution gave the cyclic trimer [W3O3(μ-O)3Cl6(OPMe3)3], the structure of which revealed a six-membered W3O3 ring core with very asymmetric oxido-bridges. The structure of the tungsten(V) complex [WOCl3(2,2′-bipy)] is also reported.
Substitution of conventional high-temperature syntheses of inorganic compounds by near-room-temperature syntheses in ionic liquids
Groh, Matthias F.,Muller, Ulrike,Ahmed, Ejaz,Rothenberger, Alexander,Ruck, Michael
, p. 1108 - 1122 (2013/12/04)
The high-temperature syntheses of the low-valent halogenides P2I4, Te2Br, a-Te4I4, Te4(Al2Cl7)2, Te4(Bi6Cl20), Te8(Bi4Cl14), Bi8(AlCl4)2, Bi6Cl7, and Bi6Br7, as well as of WSCl4 andWOCl4 have been replaced by resource-efficient low-temperature syntheses in room temperature ionic liquids (RTILs). The simple one-pot syntheses generally do not require elaborate equipment such as twozone furnaces or evacuated silica ampoules. Compared to the published conventional approaches, reduction of reaction time (up to 80%) and temperature (up to 500 K) and, simultaneously, an increase in yield were achieved. In the majority of cases, the solid products were phase-pure. X-Ray diffraction on single crystals (redetermination of 11 crystal structures) has demonstrated that the quality of the crystals from RTILs is comparable to that of products obtained by chemical transport reactions.
