Synthese, Struktur und Eigenschaften der Nonachloroditellur(IV)- und Tetrachlorohydroxotellur(IV)säure-Hydrate. Kristallstrukturen der Oxonium-Salze [H9O4]n[Te2Cl9]n und [H9O4][TeCl4OH ] · H2O/Synthesis, Structure and Properties of Nonachloroditellurous and Tetrachlorohydroxotellurous Acid Hydrates. Crystal Structures of the Oxonium Salts [H9O4]n[Te2Cl9]n und [H9O4][TeCl4OH ] · H2O

1992 ◽  
Vol 47 (1) ◽  
pp. 93-103 ◽  
Author(s):  
Bernt Krebs ◽  
Stefan Bonmann ◽  
Klaus Gretenkord

Light yellow needles of crystalline nonachloroditellurous acid with the formal composition HTe2Cl9 · 4H2O (1) (space group C2/c, a = 11.642(6), b = 13.012(4), c = 12.663(5) Å, β = 119.64(3)° at 140 K) were isolated from a saturated solution of TeCl4 in conc. HCl. From a solution of more diluted HCl the acid HTeCl4OH · 5H2O (2) could be prepared (space group P212121, a = 7.065(3), b = 8.551(2), c = 18.192(6)Å at 140 K). 1 is the first acid isolated from the system TeCl4 /HCl/H2O with a polymeric anion. The novel polynuclear [Te2Cl9]nn- chains are built from alternately corner-sharing and edge-sharing distorted octahedral TeCl6 units. The mean bond distances are 2.356 Å for terminal Te-Cl and 2.805 Å for Te-μ2Cl. 2 contains square-pyramidal [TeCl4OH]- anions with oxygen in the apical position (Te-Cl: 2.447-2.552 Å; Te-O: 1.926 Å). The cations in both structures are [H9O4]+ hydroxonium ions (O···O (1): 2.47(3), 2.55(2) and 2.57(1) Å; O···O (2): 2.550(4), 2.584(4) and 2.588(5) Å). Thus the formulae of the acids have to be written as [H9O4]n[Te2Cl9]n and [H9O4][TeCl4OH] · H2O. Raman spectra of both compounds are reported.

1984 ◽  
Vol 39 (12) ◽  
pp. 1633-1641 ◽  
Author(s):  
Bernt Krebs ◽  
Andreas Schäffer ◽  
Siegfried Pohl

The novel anion SeBr42- was prepared by dissociation of SeOBr2 with formation of SeBr2 and subsequent reaction with bromide in acetonitrile solution; it was isolated as the crystalline tetraphenylphosphonium salt. The X-ray structure analysis of [P(C6H 5)4]2SeBr4 (space group P 1̄ , a = 14.190(3), b = 15.125(3), c = 10.383(2) Å , α = 92.69(2), β = 100.89(2), γ = 92.04(2)° Å , V = 2182.2 Å3) shows the structure to contain monomeric SeBr42- anions with a square planar coordination of Se(II). The mean Se -Br bond length in the anion is 2.598 Å .[P(C6H5)4]2Se2Br6 was obtained from the reaction of SeBr4 (which is in equilibrium with SeBr2, Se2Br2, and Br2, in solution) and bromide in acetonitrile. It crystallizes in the space group P 1̄, with a = 1 0 . 9 3 3 ( 4 ) , = 11.154(4), c = 10.344(4) Å , α = 79.26(3), β = 72.63(3), y = 81.35(3)°, γ = 1176.7 Å3 (at -120 °C), and contains a novel type of centrosymmetric Se2Br62- ions with square planar Se-coordination. The mean terminal and bridging Se -Br bond lengths are 2.442 and 2.799 Å , resp. Vibrational spectra are reported and discussed.


1999 ◽  
Vol 54 (4) ◽  
pp. 441-446 ◽  
Author(s):  
Kurt O. Klepp ◽  
Andreas Kolb

The isostructural compounds K2ZrTe3 and Rb2ZrTe3 were obtained at 1000°C by reacting K2Te and Rb2Te with stoichiometric amounts of Zr and Te. The compounds are monoclinic, mP24, space group P21/c, Z = 4 with a = 9.089(3), b = 14.148(4), c = 6.986(3) Å, β = 105.90( 1)° and a = 9.735(4), b = 14.300(7), c = 6.952(8) Å, β = 108.61(2)°, respectively. The crystal structure was determined from diffractometer data and refined to R = 0.030 for 1452 Fo's for K2ZrTe3 and R = 0.038 for 1131 Fo's for Rb2ZrTe3. The crystal structure is of a new type, characterized by infinite anionic chains, 1∞-[ZrTe3]2- built up by octahedra sharing opposite faces which run along [001]. The mean Zr-Te bond lengths are 2.921 and 2.920 Å, respectively. The alkali cations separating the chains are characterized by two different - distorted octahedral and pentagonal bipyramidal - chalcogen environments.


Author(s):  
James Louis-Jean ◽  
Samundeeswari Mariappan Balasekaran ◽  
Dean Smith ◽  
Ashkan Salamat ◽  
Chien Thang Pham ◽  
...  

The A 2[ReF6] (A = K, Rb and Cs) salts are isotypic and crystallize in the trigonal space group type P\overline{3}m1, adopting the K2[GeF6] structure type. Common to all A 2[ReF6] structures are slightly distorted octahedral [ReF6]2− anions with an average Re—F bond length of 1.951 (8) Å. In those salts, symmetry lowering on the local [ReF6]2− anions from Oh (free anion) to D 3d (solid-state structure) occur. The distortions of the [ReF6]2− anions, as observed in their Raman spectra, are correlated to the size of the counter-cations.


1992 ◽  
Vol 70 (3) ◽  
pp. 919-925 ◽  
Author(s):  
A. Wallace Cordes ◽  
Charles M. Chamchoumis ◽  
Robin G. Hicks ◽  
Richard T. Oakley ◽  
Kelly M. Young ◽  
...  

The preparation and solid state characterization of the bifunctional radical furan-2,5-bis(1,2,3,5-dithiadiazolyl) 2,5-[(S2N2C)OC4H2(CN2S2)] and the related monofunctional radical 2-cyanofuran-5-(1,2,3,5-dithiadiazolyl) 2,5-[(S2N2C)OC4H2(CN)] are described. The crystal structure of 2,5-[(S2N2C)OC4H2(CN2S2)] is orthorhombic, space group Pna21, and consists of interleaved arrays of dimers, for which the mean interannular [Formula: see text] contact is 3.137 Å. The crystal structure of the monofunctional radical 2,5-[(S2N2C)OC4H2(CN)] is monoclinic, space group P21/n, and consists of a ribbon-like network of dimers (mean interannular [Formula: see text] interconnected by close head-to-tail [Formula: see text] contacts. The dimer units form stacks parallel to z, with a mean interdimer [Formula: see text] separation of 3.956 Å. The similarities and differences between these two crystal structures and those of related benzene-substituted systems are discussed. Keywords: dithiadiazolyl radicals, furan-based diradicals, cyanofuran-based radicals, radical dimers, crystal structures.


2011 ◽  
Vol 66 (4) ◽  
pp. 359-365 ◽  
Author(s):  
Olaf Reckeweg ◽  
Armin Schulz ◽  
Francis J. DiSalvo

Single crystals of Eu5(BO3)3Cl were obtained by serendipity by reacting Eu2O3 and Mg with B2O3 at 1300 K in the presence of an NaCl melt for 13 h in silica-jacketed Nb ampoules. Ba5(BO3)3X (X = Cl, Br) crystals were formed by direct synthesis from appropriate amounts of Ba(OH)2, H3BO3 and the respective barium halide (hydrate) in alumina crucibles kept in the open atmosphere at 1300 K for 13 h. The crystal structures of the title compounds were determined with single-crystal X-ray diffraction. All compounds crystallize isotypically to Sr5(BO3)3Cl in the orthorhombic space group C2221 (no. 20, Z = 4) with the lattice parameters a = 1000.34(7), b = 1419.00(9), c = 739.48(5) pm for Eu5(BO3)3Cl, a = 1045.49(5), b = 1487.89(8), c = 787.01(4) pm for Ba5(BO3)3Cl, and a = 1048.76(7), b = 1481.13(9) and c = 801.22(5) pm for Ba5(BO3)3Br. The Raman spectra of all compounds were acquired and are presented and compared to literature data. The incremental volume of the orthoborate (BO3)3− anion has been determined and is compared to the Biltz volume


2001 ◽  
Vol 65 (4) ◽  
pp. 523-531 ◽  
Author(s):  
A. Kyono ◽  
M. Kimata

AbstractThe crystal structure of hydrothermally synthesized Rb-feldspar (monoclinic, space group C2/m, a= 8.839(2)Å, b= 13.035(2)Å, c= 7.175(2)Å, β = 116.11(1)8, V= 742.3(3)Å3, Z= 4) has been refined to a final R of 0.0574 for 692 independent X-ray reflections. Microprobe analyses of the Rb-feldspar suggest deviation from stoichiometry, with excess Si and Al, resulting in a unit formula of Rb0.811□0.127Al1.059Si3.003O8. Infrared (IR) spectra indicate the structural occupancy of large H2O content, which implies that the □Si4O8 substitution favours the structural incorporation of the H2O molecule at the M-site. The mean T–O distances are 1.632 Å for T1 and 1.645 Å for T2, revealing highly disordered (Al,Si) distribution with Al/Si = 0.245/0.755 (T1 site) and 0.255/0.745 (T2 site).There are two geochemical implications from this refinement: (1) identification of both rubicline triclinic with (Al,Si) ordered distribution and synthetic monoclinic RbAlSi3O8 with (Al,Si) disordered distribution implies that Rb cannot be one of factors disrupting the (Al,Si) ordered and disordered distributions in feldspars; and (2) natural and synthetic feldspars capable of accommodating the large cations tend to incorporate □Si4O8, excess Al and H2O components in their crystal structures.


1994 ◽  
Vol 33 (18) ◽  
pp. 3849-3851 ◽  
Author(s):  
Pradip Bakshi ◽  
Paul D. Boyle ◽  
T. Stanley Cameron ◽  
Jack Passmore ◽  
Gabriele Schatte ◽  
...  

2006 ◽  
Vol 84 (7) ◽  
pp. 971-978 ◽  
Author(s):  
Soria Meghdadi ◽  
Mehdi Amirnasr ◽  
Vratislav Langer ◽  
Alison Zamanpoor

Cobalt(II), nickel(II), copper(II), and two cobalt(III) complexes of a new dianionic ligand, bqb, [H2bqb = N,N'-bis(2-quinolinecarboxamide)-1,2-benzene] have been synthesized and characterized by elemental analyses, IR, and 1H NMR spectroscopy. The crystal and molecular structures of the [Ni(bqb)] (2) and [N(n-Bu)4][CoIII(bqb)(N3)2] (5) complexes were determined by X-ray crystallography. Complex 2 crystallizes in the monoclinic space group C2/c with a distorted square-planar structure including two short Ni–N (1.848 Å) and two long Ni–N (1.958 Å) bonds. The structure consists of sheets formed in the plane parallel to the b axis and diagonal to vectors a and c by intermolecular hydrogen bonds. Complex 5 crystallizes in the monoclinic space group C2 with a distorted octahedral structure. The [N(n-Bu)4]+ ion is disordered at the C3A and C4A atoms of one Bu. The IR and 1H NMR spectra of the complexes are also discussed.Key words: N4-dianionic amido ligand (bqb), (bqb) complexes of Co(II), Ni(II), Cu(II), and Co(III), azide, cyanide, X-ray crystal structures.


1980 ◽  
Vol 35 (11) ◽  
pp. 1344-1348 ◽  
Author(s):  
Joachim Fuchs ◽  
Hernan Guevara

Abstract KHAs2O4 · 1/2 H2O crystallizes in the tetragonal space group I 4/m with the lattice constants a = 14,480 Å, c = 5,250 Å. The anion forms infinite chains, [HAs2O4]nn- , in the direction of the c axis. Arsenic is surrounded by three oxygens in trigonal pyramidal co-ordinations. Ultracentrifuge work shows that the solution contains monomeric species, probably [ASO(OH)2]-. Raman spectra gave no evidence for the existence of As-H-bonds either in the solid or in solution.


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