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Amorphous titanium phosphate ion-exchangers are often of a “mixed type”, i.e., they contain a mixture of –HPO4 and –H2PO4 active groups. Their synthesis requires careful handling to obtain the same proportion of active units and sorption characteristics. This article focuses on the influence of titanium sources and post-synthetic treatments on the uniform synthesis of amorphous TiP1 (TiO(OH)(H2PO4)·H2O). It also describes a mild and straightforward method for obtaining crystalline α-TiP (Ti(HPO4)2·H2O). Amorphous TiP1 was successfully synthesized using five sources of titanium providing that the content of titanium and H2SO4 in the primary solution was 60–110 g L−1 and 400 ± 50 g L−1, respectively. Observations revealed that organic and inorganic acids could also be comparably used in post-synthetic treatments to protonate the phosphate groups into –H2PO4 units. The Na+ uptake (up to 7.2 meq g−1) and ion-exchange capacities towards divalent ions (up to 3.8 meq g−1) of all the TiP1-type sorbents studied are among the highest reported for TiP systems. Despite differences in the surface characteristics, the TiP1 materials synthesized in this study displayed comparable sorption properties, supporting the fact that chemisorption is the governing factor behind the sorption processes. Crystalline α-TiP is obtained under similar mild synthesis conditions when the P2O5 : TiO2 molar ratio is greater than 1 : 1, regardless of the titanium source. The possibility of using various types of TiOSO4 as a titanium source for TiP1 and α-TiP syntheses is emphasized and all reported data are re-considered from a synthetic perspective. [ABSTRACT FROM AUTHOR]

Abstract: Polycrystalline tetra-nuclear Cu4[S2P(O-i-C3H7)2]4, hexa-nuclear Cu6[S2P(OC2H5)2]6, and octa-nuclear Cu8[S2P(O-i-C4H9)2]6(S) complexes were synthesized and analyzed by means of solid-state 31P CP/MAS and 65Cu static NMR spectroscopy. The symmetries of the electronic environments around each P-site were estimated from the 31P chemical shift anisotropy (CSA) parameters, Δ aniso and η. The 65Cu chemical shift and quadrupolar splitting parameters obtained from the experimental 65Cu NMR spectra of the polycrystalline CuI-complexes are presented. A solid-state NMR approach for the elucidation of the stereochemistry of poly-nuclear Cu(I) dithiophosphate complexes, when the structural analysis of the systems by single-crystal X-ray diffraction is not readily available, is proposed. [Copyright &y& Elsevier]

In the title compound, [Ru(C10H10N6)(C7H10N2)3](PF6)2·C4H10O, the Ru(II) cation is coordinated by one tris-(1-pyrazol-yl)methane (Tpm) and three dimethylaminopyridine (dmap) ligands in a slightly distorted octa-hedral geometry. The asymmetric unit consists of one complex cation, two hexa-fluorido-phosphate anions and one diethyl ether solvent mol-ecule in general positions. Although quite a large number of ruthenium complexes of the facially coordinating tridentate Tpm ligand have been structurally characterized, this is only the second one containing three pyridyl co-ligands. The average Ru-N(Tpm) distance is 2.059 (12) Å, while the average Ru-N(dmap) [dmap = 4-(di-methyl-amino)-pyridine] distance is somewhat longer at 2.108 (13) Å. The orientation of the dmap ligands varies greatly, with dihedral angles between the pyridyl and opposite pyrazolyl rings of 14.3 (2), 23.2 (2) and 61.2 (2)°.

A number of polycrystalline copper(I) O,O'-dialkyldithiophosphate cluster compounds with Cu4, Cu6, and Cu8 cores were synthesized and characterized by using extended X-ray absorption fine-structure (EXAFS) spectroscopy. The structural relationship of these compounds is discussed. The polycrystalline copper(I) O,O'-diisobutyldithiophosphate cluster compounds, [Cu8{S2P(OiBu)2}6(S)] and [Cu6{S2P(OiBu)2}6], were also characterized by using 31P CP/MAS NMR (CP = cross polarization, MAS = magic-angle spinning) and static 65Cu NMR spectroscopies (at different magnetic fields) and powder X-ray diffraction (XRD) analysis. Comparative analyses of the 31P chemical-shift tensor, and the 65Cu chemical shift and quadrupolar-splitting parameters, estimated from the experimental NMR spectra of the polycrystalline copper(I) cluster compounds, are presented. The adsorption mechanism of the potassium O,O'-diisobutyldithiophosphate collector, K[S2P(OiBu)2], at the surface of synthetic chalcocite (Cu2S) was studied by means of solid-state 31P CP/MAS NMR spectroscopy and scanning electron microscopy (SEM). 31P NMR resonance lines from collector-treated chalcocite surfaces were assigned to a mixture of [Cu8{S2P(OiBu)2}6(S)] and [Cu6{S2P(OiBu)2}6] compounds.

The interactions of synthetic chalcocite surfaces with diethyldithiophosphate, potassium salt, K[S2P(OC2H5)2], were studied by means of 31P cross-polarization/magic angle spinning (CP/MAS) NMR spectroscopy and scanning electron microscopy (SEM). To identify the species formed on the Cu2S surfaces, a polycrystalline {CuI6[S2P(OC2H5)2]6} cluster was synthesized and analyzed by SEM, powder X-ray diffraction techniques and solid-state 31P CP/MAS NMR and static 65Cu NMR spectroscopy. 31P chemical shift anisotropy (CSA) parameters, delta(cs) and eta(cs), were estimated and used for assigning the bridging type of diethyldithiophosphate ligands in the {CuI6[S2P(OC2H5)2]6} cluster. The latter data were compared to 31P CSA parameters estimated from the spinning sideband patterns in 31P NMR spectra of the collector-treated mineral surfaces: formation of polycrystalline {CuI6[S2P(OC2H5)2]6} on the Cu2S surfaces is suggested. The second-order quadrupolar line shape of 65Cu was simulated, and the NMR interaction parameters, CQ and etaQ, for the copper(I) diethyldithiophosphate cluster were obtained.