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1.
Twenty-five zirconium (hafnium) fluoride compounds have been synthesized at room temperature in the systems MO2-H2SO4-M′nA(HF)-H2O (M = Zr (Hf); M′ = Na, K, Rb, Cs, NH4; A = F, SO4) and their X-ray luminescence spectra (luminescence wavelengths and relative intensities) have been measured. The X-ray luminescence of the compounds has been considered as a function of the composition (cations, anions, water content) and different structural factors (CNs, polyhedra, H-bonds). Ammonium compounds do not luminesce, and sodium fluorozirconates and heptafluorozirconates are weakly luminescing. Hexafluorozirconates M2Zr(Hf)F6 (M= K, Rb, Cs) and M5Zr4F21 · 3H2O (M = Rb, Cs), as well as oxofluorozirconate Rb2Zr3OF12, are strongly luminescing compounds.  相似文献   

2.
Zintl-Compounds with Gold: M3AuSn4 with M = K, Rb, Cs and M3AuPb4 with M = Rb, Cs Silver coloured, brittle single crystals of the compounds M3AuSn4 with M = K, Rb, Cs and M3AuPb4 with M = Rb, Cs were synthesized by reactions of alkali metal azides (MN3) with gold sponge and tin (lead) powder at T = 923 K. The structures of the isotypic compounds (space group Pmmn, Z = 2) were determined from X-ray single-crystal diffractometry data (see ‘‘Inhaltsübersicht”︁”︁). The Zintl-compounds M3AuE(14)4 with E(14) = Sn, Pb contain [AuE(14)4]-chains with P4-analogous E(14)4-tetrahedra which are connected by μ2-bridging gold atoms.  相似文献   

3.
The phase composition of the M2O-ZnO-V2O5 (M = Li, Na, K, Rb, Cs) systems at subsolidus temperatures is investigated. Three groups of double vanadates are identified: M2Zn(VO3)4 for M = K, Rb, or Cs; M2ZnV2O7 for M = Na, K, or Rb; and MZnVO4 for M = Li or Cs. Double pyrovanadate Rb2ZnV2O7 is synthesized for the first time. Phase diagrams are designed for all systems. Comparative phase-formation features of the systems in the alkali oxide series are considered.  相似文献   

4.
Trioxotrifluoroosmates(VIII) M[OsO3F3] (M = Cs, Rb, K) have been prepared by direct combination of OsO3F2 and the appropriate alkali fluoride MF. The reaction of OsO4 with M′F (M′ = Cs, Rb) in aqueous solution produces the tetraoxodifluoroosmates(VIII) M′2[OsO4F2]. On the basis of their vibrational spectra the assignment of a fac (C3v) structure to [OsO3F3]? and a cis (C2v) to [OsO4F2]2? is proposed. The electronic spectra of the anions have been recorded and are interpreted using the optical electronegativity concept.  相似文献   

5.
Result of a study of how antimony trifluoride and fluoride complexes MSb2F7 (M = K, Rb, Cs, Tl, NH4), MSbF4 (M = Na, K, Rb, Cs, NH4), and M2SbF5 (M = Na, K, Rb, Cs, Tl, NH4) affect the growth of associations of marine bacteria and vital activity of marine alga Ulva Fenestrata are presented. The possible ways of using Sb(III) fluoride compounds are discussed.  相似文献   

6.
The alkaline 1-phenyl-1H-1, 2, 3, 4-tetrazole-5-thiolate salts, M[C6H5N4CS] (M = Li ( 1 ), Na ( 2 ), K ( 3 ), Rb ( 4 ) and Cs ( 5 )) were obtained and characterized by means of mass spectrometry (FAB+) and NMR (1H; 13C) spectroscopy. The structures of Na ( 2 ), K ( 3 ), Rb ( 4 ) and Cs ( 5 ) compounds were determined by X-ray diffraction methods. The ligand shows a rich variety of coordination patterns with the alkaline cations. The formation of a four-membered ring MSCN in the compounds with heavier alkali cations (K, Rb and Cs) is shown. In all the cations the coordination number around it increases with the ionic radius. Compounds with Cs+ and Rb+ exhibited the formation of Cs-C and Rb-C interactions with the phenyl group.  相似文献   

7.
Preparation, X-Ray and 1 H-Wide-Line-Resonance Studies of Alkali Germyl Compounds, GeH 3 M The alkali germyls GeH 3 M (M = Li, Na, K, Rb, Cs) have been prepared from germane and the corresponding alkali metals. GeH 3 K, GeH 3 Rb and GeH 3 Cs could be obtained as crystalline solids. It has been shown from X-ray single-crystal studies that GeH 3 Cs has a structure of the TlI-type with the unusual coordination number 7. 1 H-wide-line-resonance investigations show that the rotations of the germyl groups are frozen in at low temperatures. From the observed 2. moment of the fixed germyl groups a H? Ge? H valence augle of 92.5±4°has been determined.  相似文献   

8.
A complete series of alkali metal 1,3-dimethylviolurates M(Me2Vio) was synthesized and fully characterized. The title compounds M(Me2Vio)(H2O) [M = Li ( 3 ), Na ( 4 )], K(Me2Vio)(H2O)0.5 ( 5 ) and M(Me2Vio) [M = Rb ( 6 ), Cs ( 7 )] were prepared by neutralizing 1,3-dimethylvioluric acid (= HMe2Vio; 2 ) with 1 equiv. of the corresponding metal hydroxides MOH. The resulting salts exhibit striking colors ranging from orange-red ( 3 ) through purple ( 4 , 5 ) to bright blue ( 6 , 7 ). In contrast to the monohydrate 4 , the classical synthesis of sodium 1,3-dimethylviolurate from 1,3-dimethylbarbituric acid and NaNO2 afforded the purple trihydrate Na(Me2Vio)(H2O)3 ( 4a ). All new compounds have been fully characterized by their IR and NMR (1H, 13C) spectra as well as elemental analyses. X-ray crystal structure determination revealed that the title compounds exist as one- (Li, Na), two- (K, Cs), or three-dimensional (Rb) coordination polymers in the solid state.  相似文献   

9.
Reaction of alkali metal ozonides (KO3, RbO3 and CsO3) with [18]crown‐6 in liquid ammonia yields compounds of the composition M([18]crown‐6)O3·x NH3 with M = K (x = 2), Rb (x = 1) and Cs (x = 8). The large intermolecular distance between adjacent radical anions in these compounds leads to almost ideal paramagnetic behavior according to Curie's law. Discrepancies concerning the structure of the ozonide anions in the K and Cs compound compared to a former investigation on Rb([18]crown‐6)O3·NH3 have been resolved by means of DFT calculations and a single‐crystal structure redetermination.  相似文献   

10.
Ammonium-containing zirconium fluoride complexes of the formula (NH4)6MZr4F23 (M = K, Rb, and Cs) were obtained and studied. The complexes crystallize in the orthorhombic system. Their unit cell parameters were determined. The IR absorption spectra of the complexes in the 350–4000 cm?1 range were recorded and examined.  相似文献   

11.
On Chalcogenolates. 96. Studies on Trimethylsilyl Carbonates of Alkali Metals The trimethylsilyl carbonates M[O2COSi(CH3)3] with M = Li, Na, K, Rb, Cs have been prepared by reaction of Co2 with the corresponding silanolate. Infrared spectra, electron absorption spectra, 1H-NMR spectra as well as mass spectra are communicated. In aqueous solution the equivalent conductivities of [O2COSi(CH3)3]? have been determined by means of conductivity measurements. The diffusion coefficient of the ion was calculated. The dissociation constant of trimethylsilyl carbonic acid in water at 20°C is Ka = (4,83 ± 0,5) · 10?10. The thermodynamic data of the dissociation were calculated.  相似文献   

12.
On Fluorides of Divalent Lanthanoids. II. Synthesis of MLnF3 from MLnF4 CsEuF3, CsYbF3, and RbYbF3, which had already been prepared via reduction of the corresponding trifluorides with alkali metal, were also obtained by reducing MLnF4 with M (M = Cs, Rb, K; Ln = Eu, Yb). No additional alkali fluoroperovskites of lanthanoids were detected either by reduction of LnF3 or MLnF4 with metallic Cs, Rb, or K or by other reactions, e.g. 3CsF + 2SmF3 + Sm. It was shown that the reaction of CsF with EuF2 (350–850°C) produced only very little CsEuF3.  相似文献   

13.
On the Tetrabromothallates MTlBr4 (M = K, Rb, Cs, NH4) The tetrabromothallates MTlBr4 (M = K, Rb, Cs, NH4) were obtained by dehydratisation of the appropriate hydrates MTlBr4 · nH2O and by the reaction of TlBr, MBr, and Br2 in closed glass tubes at 400°C. KTlBr4 and NH4TlBr4 crystallize orthorhombic in the Ga[GaCl4]-type with the following lattice constants a = 795.2(3), b = 1036.0(4), c = 1042.1(5) pm (KTlBr4), and a = 812.6(3), b = 1070.1(13), c = 1110.6(10) pm (NH4TlBr4), respectively.  相似文献   

14.
Crystallographic data and IR Raman spectra are presented for a new series of compounds, M3ScF6 (M Na, K, Rb, Cs, T1). Spectral assignments are proposed and effects of the cation on vibrational modes is discussed. Preliminary temperature-dependant Raman spectra are presented and correlated with DSC and crystallographic data.  相似文献   

15.
Ammonium-containing hafnium fluoro complexes (NH4)6MHf4F23 (M = K, Rb, Cs), which crystallize in orthorhombic symmetry, were synthesized and studied. Their unit cell parameters were determined. The IR absorption spectra of the synthesized complexes were studied in the region of 350?C4000 cm?1.  相似文献   

16.
The hexagonal, tetragonal and pyrochlore-type nonstoichiometric iron fluorides MxFeF3 (M = K, Rb, Cs, NH4) have been studied by Mössbauer spectroscopy over the temperature range 4.2 to 295 K. The magnetic transition temperatures have been determined. The ferrous and ferric ions remain in discrete oxidation states indicating the absence of charge hopping. The broadened lines of the spectra of the hexagonal and tetragonal phases are consistent with the disordering of Fe2+ and Fe3+ in the structure. By contrast, the narrow linewidths of the spectra of the pyrochlore-type phases characterize a structural ordering between the ferrous and ferric ions.  相似文献   

17.
Nanorods of vanadium oxide doped with alkali metal ions M x V2O5 · nH2O (M = Na, K, Rb, Cs, x = 0.31–0.44) have been obtained under hydrothermal conditions. The particles are 30–80 nm in diameter and a few micrometers in length. The chemical state of atoms and their concentration ratios have been studied by XPS. It has been shown that vanadium atoms are in two oxidation states V5+ and V4+ and the concentration of vanadium(IV) ions directly depends on the alkali metal. The X-ray photoelectron spectra of the valence bands of M x V2O5 · nH2O (M = Na, K, Rb, Cs) nanorods have been measured and interpreted.  相似文献   

18.
Zintl‐Compounds with Gold and Germanium: M3AuGe4 with M = K, Rb, Cs Black, brittle single crystals of M3AuGe4 with M = K, Rb, Cs were synthesized by reactions of alkali metal azides (MN3) with gold sponge and germanium powder at T = 1120 K. The structures of the compounds (space group Pmmn, Z = 2, K3AuGe4: a = 6.655(1)Å, b = 11.911(2)Å, c = 6.081(1)Å; Rb3AuGe4: a = 6.894(1)Å, b = 12.421(1)Å, c = 6.107(1)Å; Cs3AuGe4: a = 7.179(1)Å, b = 12.993(2)Å, c = 6.112(2)Å) were determined from X‐ray single‐crystal diffractometry data. The semiconducting compounds contain equation/tex2gif-stack-2.gif[AuGe4]‐chains with P4‐analogous Ge4‐tetrahedra which are connected by μ2‐bridging gold atoms in a distorted tetrahedral Ge‐coordination.  相似文献   

19.
On the Oxides A2PbO3 (A = K, Rb, Cs) The oxides A2PbO3 (A = K, Rb, Cs) have been reinvestigated [four-circle diffractometer PW 1100 (Fa. Philips), all particles ?anisotropically”? refined, parameters see text]. The structural features are confirmed, whereas the results on space group and parameters have to be partially corrected.  相似文献   

20.
On Chalcogenolates. 120. Synthesis and Properties of N-Cyanguanidino Monothioformates N-Cyanguanidine reacts with COS in the presence of the corresponding alkali metal hydroxide to form N-cyanguanidino monothioformates M[SOC? NH? C(NH2)?N? CN]. The compounds with M = K, Rb, Cs and the methyl ester have been characterized by means of electron absorption, 1H and 13C NMR, infrared, and mass spectra.  相似文献   

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