Beiträge zur Kristallchemie und zum thermischen Verhalten von wasserfreien Phosphaten. XXXIII [1] In2P2O7, ein Indium(I)‐diphosphato‐indat(III) und In4(P2O7)3 — Darstellung,Kristallisation und Kristallstrukturen

Contributions on Crystal Chemistry and Thermal Behaviour of Anhydrous Phosphates. XXXIII [1] In₂P₂O₇ an Indium(I)‐diphosphatoindate(III), and In₄(P₂O₇)₃ — Synthesis, Crystallization, and Crystal Structure Solid state reactions via the gas phase lead to the new mixed‐valence indium(I, III)‐diphosphate In₂P₂O₇. Colourless single crystals of In₂P₂O₇ have been grown by isothermal heating of stoichiometric amounts of InPO₄ and InP (800 °C; 7d) using iodine as mineralizer. The structure of In₂P₂O₇ [P2₁/c, a = 7.550(1) Å, b = 10.412(1) Å, c = 8.461(2) Å, b = 105.82(1)°, 2813 independent reflections, 101 parameter, R1 = 0.031, wR2 = 0.078] is the first example for an In⁺ cation in pure oxygen coordination. Observed distances d(In^I‐O) are exceptionally long (d_min(In^I‐O) = 2.82 Å) and support assumption of mainly s‐character for the lone‐pair at the In⁺ ion. Single crystals of In₄(P₂O₇)₃ were grown by chemical vapour transport experiments in a temperature gradient (1000 → 900 °C) using P/I mixtures as transport agent. In contrast to the isostructural diphosphates M₄(P₂O₇)₃ (M = V, Cr, Fe) monoclinic instead of orthorhombic symmetry has been found for In₄(P₂O₇)₃ [P2₁/a, a = 13.248(3) Å, b = 9.758(1) Å, c = 13.442(2) Å, b = 108.94(1)°, 7221 independent reflexes, 281 parameter, R1 = 0.027, wR2 = 0.067].     

Beiträge zum Koordinationsverhalten von Oxidionen in anorganischen Feststoffen. III [1] Mn2P2O7, Mn2P4O12 und Mn2Si(P2O7)2 — Kristallzüchtung,Strukturverfeinerungen und Elektronenspektren von Mangan(II)‐Phosphaten

Contributions on the Bonding Behaviour of Oxygen in Inorganic Solids. III [1] Mn₂P₂O₇, Mn₂P₄O₁₂ und Mn₂Si(P₂O₇)₂ — Crystal Growth, Structure Refinements and Electronic Spectra of Manganese(II) Phosphates By chemical vapour transport reactions in a temperature gradient single crystals of Mn₂P₂O₇ (1050 → 950 °C) and Mn₂P₄O₁₂ (850 → 750 °C) have been obtained using P/I mixtures as transport agent. Mn₂Si(P₂O₇)₂ was crystallized by isothermal heating (850 °C, 8d; NH₄Cl as mineralizer) of Mn₂P₄O₁₂ und SiO₂. In Mn₂Si(P₂O₇)₂ [C 2/c, a = 17.072(1)Å, b = 5.0450(4)Å, c = 12.3880(9)Å, β = 103.55(9)°, 1052 independent reflections, 97 variables, R1 = 0.023, wR2 = 0.061] the Mn²⁺ ions show compressed octahedral coordination (d¯_Mn—O = 2.19Å). The mean distance d¯_Mn—O = 2.18Å was found for the radially distorted octahedra [MnO₆] in Mn₂P₄O₁₂ [C 2/c, Z = 4, a = 12.065(1)Å, b = 8.468(1)Å, c = 10.170(1)Å, β = 119.29(1)°, 2811 independent reflections, 85 variables, R1 = 0.025, wR2 = 0.072]. Powder reflectance spectra of the three pink coloured manganese(II) phosphates have been measured. The spectra show clearly the influence of the low‐symmetry ligand fields around Mn²⁺. Observed d—d electronic transition energies and the results of calculations within the framework of the angular overlap model (AOM) are in good agreement. Bonding parameters for the manganese‐oxygen interaction in [Mn²⁺O₆] chromophors as obtained from the AOM treatment (B, C, Trees correction α, e_σ, e_π) are discussed.     

Bariumstannat‐Pulver durch hydrothermale Synthese und durch Thermolyse von Bariumzinn(IV)‐glykolaten. Synthese und Struktur von [Ba(C2H6O2)4][Sn(C2H4O2)3] und [Ba(C2H6O2)2][Sn(C2H4O2)3]·CH3OH

Barium Stannate Powders from Hydrothermal Synthesis and by Thermolysis of Barium‐Tin(IV)‐Glycolates. Synthesis and Structure of [Ba(C₂H₆O₂)₄][Sn(C₂H₄O₂)₃] and [Ba(C₂H₆O₂)₂][Sn(C₂H₄O₂)₃]·CH₃OH The hydrothermal reaction as well as the microwave assisted hydrothermal reaction of SnO₂·aq with barium hydroxide gives Ba[Sn(OH)₆] ( 1 ) as powder with bar like particles. Compound 1 of the same morphology can also be isolated from a hydrothermal reaction of [Ba(C₂H₆O₂)₄][Sn(C₂H₄O₂)₃] ( 3 ). The reaction of SnO₂·aq with Ba(OH)₂·8H₂O in ethylene glycol yields the glycolate [Ba(C₂H₆O₂)₄][Sn(C₂H₄O₂)₃] ( 3 ), which forms in methanol the solvate [Ba(C₂H₆O₂)₂][Sn(C₂H₄O₂)₃]·CH₃OH ( 4 ). Compounds 1 , 3 and 4 react at different temperatures to BaSnO₃ ( 2 ) consisting of powders with different morphologies; because of the grain size of the resulting powders compounds 3 and 4 are suitable as precursor for the fabrication of corresponding ceramics.     

Beiträge zur Kristallchemie und zum thermischen Verhalten von wasserfreien Phosphaten. XXXVI [1] Synthese,Kristallstruktur und spektroskopische Charakterisierung von Palladium(II)‐diphosphat Pd2P2O7

Synthesis, Crystal Structure and Spectroscopical Characterization of Palladium(II)‐Diphosphate Pd₂P₂O₇ Pd₂P₂O₇ is synthesized by heating (T_max = 500 °C) stoichiometric amounts of PdO and phosphoric acid. Using chemical vapour transport experiments (850 °C → 750 °C, addition of PdCl₂) Pd₂P₂O₇ was crystallized. Pd₂P₂O₇ adopts its own structure type (C 2/c (No. 15), Z = 4, a = 13,151(2) Å, b = 5,172(1) Å, c = 8,139(1) Å, β = 97,52(1)°, 1160 independent reflections, 55 variables, R1 = 0,021 and wR2 = 0,050). Square‐planar [PdO₄]‐units are linked by diphosphate‐groups generating a 3D framework. Within this framework ribbons may be distinguished. Thus Pd₂P₂O₇ might be described as palladium(II)‐[diphosphatopalladate(II)]. The results of various spectroscopic measurements (IR, Raman, UV/VIS, ³¹P‐MAS‐NMR) are reported and discussed within the context of the crystal structure.