By replacing Mn in YCa3(MnO)3(BO3)4 with trivalent Al and Ga, two new borates with the compositions of YCa3(MO)3(BO3)4 (M=Al, Ga) were prepared by solid-state reaction. Structure refinements from X-ray powder diffraction data revealed that both of them are isostructural to gaudefroyite with a hexagonal space group P63/m. Cell parameters of a=10.38775(13)Å, c=5.69198(10)Å for the Al-containing compound and a=10.5167(3)Å, c=5.8146(2)Å for the Ga analog were obtained from the refinements. The structure is constituted of AlO6 or GaO6 octahedral chains interconnected by BO3 groups in the ab plane to form a Kagomé-type lattice, leaving trigonal and apatite-like tunnels. It is found that most rare-earth and Cr, Mn ions can be substituted into the Y3+ and M3+ sites, respectively, and the preference of rare-earth ions to locate in the trigonal tunnel is correlated to the sizes of the M3+ ions. 相似文献
Phase equilibria in the Ba3(VO4)2-K2Ba(MoO4)2 and Pb3(VO4)2-K2Pb(MoO4)2 systems have been investigated. In the first system, a continuous series of substitutional solid solutions with the palmierite
structure is formed, and in the second one, the polymorphic transition in lead orthovanadate at 100°C restricts the extent
of the palmierite-type solid solution to 10–100 mol % K2Pb(MoO4)2.
Original Russian Text ? V.D. Zhuravlev, Yu.A. Velikodnyi, A.S. Vinogradova-Zhabrova, A.P. Tyutyunnik, V.G. Zubkov, 2008, published
in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 10, pp. 1746–1748. 相似文献
The magnetic properties of Cu(NH3)4(NO3)2 have been measured at low temperatures. Broad maxima in both the susceptibility and specific heat are observed and are consistent with linear chain behavior of a Heisenberg antiferromagnet, with J/k = 3.9 ± 0.1 K. Long-range order sets in at Tc = 0.15 ± 0.01 K, and the ratio kTc/|J| = 0.038 is the lowest observed as yet for a one-dimensional, S = 1/2 antiferromagnet. 相似文献
The compounds (NH4)3[Ta(O2)4], K3[Ta(O2)4], Rb3[Ta(O2)4] and Cs3[Ta(O2)4] have been prepared and investigated by X-ray powder methods as well as Raman- and IR-spectroscopy. In the case of Rb3[Ta(O2)4] the structure has been solved from single crystal data. It is shown that all these compounds are isotypic and crystallize in the K3[Cr(O2)4] type (SG , No. 121). The infrared- and Raman spectra (recorded on powdered samples) are discussed with respect to the internal vibrations of the peroxo-group and the dodecahedral [Ta(O2)4]3− ion. Symmetry coordinates for the [Ta(O2)4]3− ion are given from which the vibrational modes of the O-O stretching vibrations of the O22− groups, the Ta-O stretching vibrations and the Ta-O bending vibrations are deduced. 相似文献
This contribution presents the results of a single crystal X-ray diffraction study of three ammine complexes of bivalent platinum
and palladium: [Pt(NH3)4](N03)2, [Pd(NH3)4](N03)2 and [Pd(NH3)4]F2H2O. The first two compounds are isostructural; metal atoms are located on inversion centers, all other atoms are in general
positions. A three-dimensional framework is built from planar-square complex cations and nitrate ions joined by N-H...O hydrogen
bonds. In [Pd(NH3)4]F2H2O, palladium atoms, as in the previous cases, are located on inversion centers, while oxygen atoms of water molecules are
on the two-fold symmetry axis. A network of strong N-H...F and O-H...F hydrogen bonds linking the cations, anions, and crystallization
water molecules is present in the structure. 相似文献
The thermal decomposition reactions were determined for [Co(en)3](N03)3 and [Co(en)3(HSO4)3 in a dynamic nitrogen gas atmosphere and vacuo, where en represents ethylenediamine. Data were obtained using thermogravimetry, DTA, thermomagnetic analysis, and mass spectrometry. The dissociation reactions in nitrogen were found to be as follows: and In vacuo, the dissociation process for [Co(en)3](N03)3 is the same as in nitrogen. Also, the decomposition of [Co(en)3](HSO4)3 is the same except for the first step which is: 相似文献
Crystals of the rhenium cluster complex (H3O)4[(C2H5)4N]6[Th2Cl4(H2O)12O]3[Re4Se4(CN)12]4 are obtained in an acidic (HCl) aqueous solution by the reaction of cluster salt K4[Re4Se4(CN)12]·6H2O with ThCl4 and (C2H5)4NCl. Single crystal X-ray analysis shows that the title compound is ionic and crystallizes in the cubic crystal system (a = 22.7322(3) ?, V = 11746.93(27) ?3, Z = 2, I4 3m space group, R = 0.0350). It contains [Th2Cl4(H2O)12O]2+ cations with two thorium atoms bonded to each other through the bridging oxygen atom forming an angle of 180° in the structure. 相似文献
A novel malonate-bridged copper (II) compound of formula {[Cu4(4,4′-bpy)8(mal)2(H2O)4](ClO4)2(H2O)4(CH3OH)2}n (4,4′-bpy = 4,4′-bipyridine; mal = malonate dianion) has been prepared and structurally characterized by X-ray crystallography.
This compound exhibits a novel three-dimensional network being composed of Cu-4,4′-bipyridine layers which are pillared by
malonate bridge ligands. The copper(II) ions has two different coordination environment. 相似文献
