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1.
On Chalcogenolates. 111. Studies on Perthiocyanic Acid. 4. Crystal and Molecular Structure of Dimethyl Perthiocyanate (CH3)2C2N2S3 crystallizes with Z = 4 in the monoclinic space group P21/c with cell dimensions a = 7.661(4) Å, b = 11.675(5) Å, c = 9.549(5) Å, β = 116.7(3)·. The crystal and molecular structure has been determined from single X-ray data at 20°C and refined to a conventional R of 0.062. The structure consists of isolated 3,5-bis(methylmercapto)-1,2,4-thiadiazole molecules. The 1,2,4-thiadiazole ring is plane and stabilized by mesomerism.  相似文献   

2.
On Chalcogenolates. 191. Esters of 2-Oxophenyldithioacetic Acid. 2. Crystal and Molecular Structure of the Methyl Ester The title compound C6H5? CO? CS? SCH3 crystallizes with Z = 2 in the triclinic space group P1 with cell dimensions (?60°C) a = 6.236(4) Å, b = 7.972(2) Å, c = 9.589(4) Å, α = 88.42(3)°, β = 75.39(5)°, γ = 81.54(4)°. The structure has been determined from single crystal X-ray data measured at ?60°C and refined to R = 0.085 and Rw = 0.087 for 2307 independent reflections. With nearly 20° the C?O bond is turned out of the plane of the phenyl ring.  相似文献   

3.
On Chalcogenolates. 170. Reaction of N,N′-Diphenyl Formamidine with Carbon Disulfide 3. Crystal Structure of Potassium N,N′-Diphenyl N-Formimidoyl Dithiocarbamate · Dioxane The title compound K[S2C? N(C6H5)? CH?NC6H5] · C4H8O2 crystallizes with Z = 4 in the monoclinic space group P21/a with cell dimensions a = 10.703(2) Å, b = 18.068(3) Å, c = 10.504(3) Å, β = 100.96(3)°. The crystal structure has been determined from single crystal X-ray data measured at 20°C and refined to a conventional R of 0.052 for 4556 independent reflections (Rw = 0.054). The K+ cation is surrounded of one oxygen, one nitrogen, and three sulfur atoms to form a distorted trigonal bipyramid. The S2CNCN part of the anion, which exists as E, E conformer, is plane. The dioxane molecule has chair conformation without symmetry centre.  相似文献   

4.
On Chalcogenolates. 118. Crystal and Molecular Structure of Oxovanadium(V) Ethylxanthate VO[S2C? OC2H5]3 crystallizes with Z = 8 in the monoclinic space group P21/n with cell dimensions a = 15.065(7) Å, b = 18.540(48) Å, c = 12.824(7) Å, = 99.31(7)°. The crystal and molecular structure has been determined from single crystal X-ray data at 20°C and refined to a conventional R of 0.045.  相似文献   

5.
Synthesis and Crystal Structure of a Novel Hexagonal Modification of Al2S3 with Five-coordinated Aluminum A new hexagonal high temperature modification of Al2S3 could be prepared by chemical vapour transport with iodine (860 → 750°C) or by annealing of α -Al2S3 at 550°C. According to the single crystal X-ray structure determination the novel form of Al2S3 crystallizes in space group P 61 (No. 169) with a = 6.491(1), c = 17.169(4) Å, V = 626.5 Å3, Z = 6; R = 0.0253. In this modification one half of the aluminum atoms are tetrahedrally coordinated [d(Al? S): 2.226–2.267 Å], whereas the other half are in trigonal bipyramidal coordination of five S atoms with bond lengths of 2.272–2.315 Å (equatorial) and 2.495–2.521 Å (axial). Aluminum in AlS5 coordination is observed for the first time in this compound. The crystal structure is isotypic to In2Se3 and AlInS3. In addition, results of a refinement of the α -Al2S3 crystal structure are reported which were obtained on crystals prepared also by chemical vapour transport with iodine.  相似文献   

6.
The reaction of K2S5, Cu, Gd, and S in a 2 : 1 : 2 : 4 molar ratio at 450 °C yields yellow-orange needle-like cuboids of the new quaternary compound KCuGd2S4. The crystal structure represents a novel three-dimensional structure type of quaternary rare earth chalcogenides with alkali metal. The compound crystallizes in the orthorhombic space group Cmcm (No. 63) with a = 3.9921(1) Å, b = 13.523(3) Å, c = 13.802(3) Å, V = 745.1(3) Å3, Z = 4. In the structure GdS6 octahedra and CuS4 tetrahedra are joined by common edges and corners forming corrugated layers parallel to (010). The GdS6 octahedra are connected via common edges in the third dimension thus leading to the formation of a three-dimensional tunnel structure. The potassium cations are confined within the pentagonal shaped channels and are surrounded by eight sulfide anions each.  相似文献   

7.
The crystal and molecular structure of 6-oxadihydrouracil (C3H4N2O3) has been determined by single crystal x-ray diffraction techniques. The compound crystallizes in the space group P21 21 21 with four molecules in a unit cell of dimensions: a = 5.106(1)Å, b = 12.461(2)Å and c = 7.112(1)Å. The structure was solved by direct methods and refined to a final value of R = 0.052. The oxauracil ring is non-planar with the C5 atom assuming tetrahedral geometry and the ring oxygen having oxazinal distances and angle (C-O = 1.432Å, N-O = 1.408Å, and CON angle of 109.0°). The usual hydrogen bonding patterns associated with the uracil ring are absent in this compound.  相似文献   

8.
Contributions to the Chemistry of Sulfur. 114. Crystal and Molecular Structures of Hexathiepane (S6CH2), Pentathiane (S5CH2), and Dibenzylpentathiane (S5C (CH2C6H5)2) The crystal and molecular structures of hexathiepane 1 , pentathiane 2 and dibenzylpentathiane 3 were determined by single crystal X-ray structure analyses. 1 : Monoclinic space group P21/c; a = 7.694(4), b = 7.668(4), c = 12.367(6) Å, β = 108.9(1)°; Z = 4, dcalc. = 1.986 g/cm3. The seven-membered heterocycle exists in twist-conformation. 2 : Monoclinic space group C2/c; a = 10.990(5), b = 6.872(4), c = 15.507(6) Å, β = 94.1(1)°; Z = 8, dcalc. = 1.982 g/cm3. The six-membered heterocycle exists in chair-conformation. 3 : Monoclinic space group P21/c; a = 12.907(8), b = 13.611(8), c = 9.408(6) Å, β = 98.9(1)°; Z = 4, dcalc. = 1.442 g/cm3. 3 is analogous to 2 a six-membered heterocycle with chair-conformation. The benzylic groups are distorted to each other. Bond lengths, bond angles, and dihedral angles of the heterocyclic sulfur rings arc discussed, especially with regard to a comparison with cyclohexasulfur, cycloheptasulfur. and cyclooctasulfur.  相似文献   

9.
The redetermination of the crystal structure of trigonal UCl6, which is the eponym for the UCl6 structure type, showed that certain atomic coordinates had been incorrectly reported. This led to noticeably different U−Cl distances within the octahedral UCl6 molecule (2.41 and 2.51 Å). Within the revised structure model presented here, which is based on single crystal data as well as quantum chemical calculations, all U−Cl distances are essentially equal within standard uncertainty (2.431(5), 2.437(5), and 2.439(6) Å). This room temperature modification, called rt-UCl6, crystallizes in the trigonal space group P m1, No. 164, hP21, with a=10.907(2), c=5.9883(12) Å, V=616.9(2) Å3, Z=3 at T=253 K. A new low-temperature (lt) modification of UCl6 is also presented that was obtained by cooling a single crystal of rt-UCl6. The phase change occurs between 150 and 175 K. lt-UCl6 crystallizes isotypic to a low-temperature modification of SF6 in the monoclinic crystal system, space group C2/m, No. 12, mS42, with a=17.847(4), b=10.8347(18), c=6.2670(17) Å, β=96.68(2)°, V=1203.6(5) Å3, Z=6 at 100 K. The Cl anions form a close-packed structure corresponding to the α-Sm type with uranium atoms in the octahedral voids. During the synthesis of UBr5 a new modification was obtained that crystallizes in the triclinic crystal system, space group P , No. 2, aP36, with a=10.4021(6), b=11.1620(6), c=12.2942(7) Å, α=68.3340(10)°, β=69.6410(10)° and γ=89.5290(10)°, V=1231.84(12) Å3, Z=3 at T=100 K. In this structure the UBr5 units are dimerized to U2Br10 molecules. The Br anions also form a close-packed structure of the α-Sm type with adjacent uranium atoms in the octahedral voids. Comparisons of the crystal structures of the compounds MX5 (M=Pa, U; X=Cl, Br) show that the crystal structure of monoclinic α-PaBr5 is probably not correct.  相似文献   

10.
Pb3Al2F12 is a fluorometalate obtained in single-crystal form by hydrothermal synthesis. It crystallizes in the monoclinic system, space group P 21/n, with a = 9.435(6) Å, b = 9.610(5) Å, c = 10.100(9) Å, β = 90.59(5)°, V = 915.7(2) Å3, Z = 4. The structure was solved from single crystal using 3 044 unique reflections (MoKα, λ = 0.71073 Å), R = 0.0463, Rw = 0.0465. The structure exhibits isolated tetrameric groups of octahedra encaged in a subnetwork of independent fluoride polyhedra and is related to that of Ba3Al2F12. A discussion about the existence and the structure of A3M2F12 compounds is given.  相似文献   

11.
On Chalcogenolates. 152. Studies on Derivatives of N-Thioformyl Dithiocarbamic Acid. 2. Crystal Structure of Tetra-n-butylammonium N-Thioformyl Dithiocarbamate The title compound [N(nC4H9)4][S2C? NH? CS? H] crystallizes with Z = 2 in the triclinic space group P1 with cell dimensions a = 9.694(2) Å, b = 11.478(3) Å, c = 12.551(6) Å, α = 63.03(3)°, β = 66.42(2)°, γ = 85.60(2)°. The crystal structure has been determined from single crystal X-ray data measured at 20°C and refined to a conventional R of 0.061 for 2249 independent reflections (Rw = 0.042). The structure is built up of dimeric aggregates consisting of 2[N(nC4H9)4]+ cations and 2[S2C? NH? CS? H]? anions. The two anions are linked together by ? CS? S…?H? N bridges. To make possible a space saving stacking of the dimeric aggregates in the crystal, one methyl group in terminal position of one n-butyl chain in the cation has gauche conformation.  相似文献   

12.
The crystal structure of 5,6,7-trimethyl-5,6,7,8-tetrahydropterine-dihydrochloride-monohydrate The crystal structure of the title compound has been determined by X-ray analysis (direct methods) and refined with 947 structure amplitudes to R = 0.026. The crystal system is orthorhombic, space group Pna21, with unit cell dimensions a = 14.081, b = 14.623, c = 6.773 Å. The molecule is protonated at the N(1)- and N(5)-position. The tetrahydropyrazine ring exists in a conformation in which C(6) deviates markedly from the mean plane of the other five atoms. The CH3-groups at N(5) and C(6) possess a trans configuration with a pseudoaxial and an axial conformation respectively. The CH3-groups at C(6) and C(7) in return possess the cis configuration, whereby the CH3-group at C(7) occupies an equatorial conformation.  相似文献   

13.
The X-ray structures at 120 K of C6H5SeO2N(CH3)2 ( 1 ) and C6H5SeO2NHCH3 ( 2 ) were determined from single crystal data, the structure of C6H5SeO2NH2 ( 3 ) was determined from a twin. The structure of ( 1 ) is composed of isolated molecules, that of ( 2 ) of dimers via H-bonds and the structure of ( 3 ) forms infinite chains. The Se? N lengths are 1.815(2) Å for ( 1 ), 1.791(2) Å for ( 2 ), and 1.781(6) Å for ( 3 ).  相似文献   

14.
Structure‐Behaviour‐Relation of Cu5Pb6O3Cl11, a Good Solid State Ionic Conductor for Cu+‐Ions A new compound within the group of coin metal lead(II) oxide halides is found and characterized by X‐ray single crystal structure determination in a temperature range from 120 K to 400 K. Cu5Pb6O3Cl11 shows a new crystal type structure with a = 21.098(4) Å, b = 10.233(2) Å, c = 12.224(2) Å, β = 124.08(3)°, Z = 4 and space group C 2/c (No. 15) at 120 K. There are found isolated oxidic chains built of OPb4 tetrahedra beside columnar areas consisting of CuCl. In this halidic partial structure are a lot of empty and partially occupied Cl4‐tetrahedra. This structural characteristic seems to be source of a very good conductivity of copper ions, like in microscopic and nanoscaled composites of Al2O3 and AgI.  相似文献   

15.
The crystal structures of the first prepared EuLnAgS3 (Ln = Gd and Ho) compounds, which have two polymorphs, were determined by X-ray powder diffraction. α-EuLnAgS3 phases are isostructural to BaErAgS3 (monoclinic crystal system, space group C2/m): a = 17.3168(10) Å, b = 3.9683(2) Å, c = 8.3174(4) Å, β = 103.94° (EuGdCuS3); a = 17.1729(12) Å, b = 3.9367(3) Å, c = 8.2905(6) Å, β = 103.9° (EuHoCuS3). β-EuLnAgS3 phases belong to the AgBiS2 structure type (cubic crystal system, space group Fm-3m): a = 5.739(2) Å (EuGdCuS3) and a = 5.678 Å (EuHoCuS3). In the α-EuLnAgS3 crystal structure, LnS6 octahedra and AgS5 trigonal bipyramids share edges to form a three-dimensional (3D) structure with channels accommodating Eu2+ ions. A decrease in Ln3+ ionic radius gives rise to the crystal-chemical contraction of the 3D structure.  相似文献   

16.
On Chalcogenolates. 161. Reaction of 1,2-Ethanedithiolates with Carbon Disulfides. 3. Crystal and Molecular Structure of 1,2-Ethane-bis(methyltrithiocarbonate) The title compound H3CS? CS? SCH2CH2S? CS? SCH3 crystallizes with Z = 2 in the triclinic space group P1 with cell dimensions a = 6.769(1) Å, b = 8,334(2) Å, c = 11.222(1) Å, α = 80.93(1)°, β = 72.01(1)°, γ = 78.58(2)°. The crystal structure has been determined from single crystal X-ray data measured at ?40°C and refined to a conventional R of 0.035 for 2004 independent reflections (Rw = 0.042). The structure consists of isolated molecules, which are linked together by weak interaction forces. The S? CS? S groups are plane.  相似文献   

17.
The molecular and crystal structure of TiMgCl6(CH3COOC2H5)4, obtained by reacting TiCl4 with a solution of MgCl2 in dry CH3COOC2H5, have been determined by x-ray diffraction. The structure was solved by direct and Fourier methods and refined by least-squares techniques to R = 0.052 for 2722 independent observed reflections. Unit-cell dimensions are a = 17.122(7), b = 9.833(3), c = 9.646(3) Å, α = 111.10(7)°, β = 107.22(6)°, γ = 103.11(6)° with Z = 2 for P1 . The titanium(IV) atom is octahedrally coordinated by six chlorine atoms (Ti? Clt = 2.293(2) Å, Ti? Clb = 2.480(2) Å) and magnesium by two chlorine atoms (Mg? Clb = 2.528(2) Å) and the carbonyl oxygen atoms of the four CH3COOC2H5 residues (Mg? O = 2.038(5) Å). The octahedra share an edge by a double chlorine bridge between the magnesium and titanium atoms. Changes in the configurations and dimensions of the free acceptor and donor molecules on adduct formation are discussed. One of the ethylacetate residues shows positional disorder, eventually with Bonding through its ethereal oxygen.  相似文献   

18.
Preparation and Crystal Structure of Na2Sn2Se5 A Novel Chalcogenostannate(IV) with Layered Complex Anions Na2Sn2Se5 was obtained from a stoichiometric mixture of Na2Se, Sn, and Se powders through a solid state reaction at 450 °C. It crystallizes orthorhombic, space group Pbca with a = 13.952(6) Å, b = 12.602(2) Å, c = 11.524(2) Å; Z = 8 and undergoes peritectic decomposition at 471(2) °C. The crystal structure was determined at ambient temperature from diffractometer data (MoKα‐radiation) and refined to a conventional R of 0.040 (1490 Fo's, 83 variables). Na2Sn2Se5 is characterized by layered complex anions running parallel to (100) which are built up by SnSe4 tetrahedra sharing common corners. The mean Sn–Se bond length calculates as 2.252(2) Å. The Na+ cations are coordinated to 6 or 7 Se in irregular configurations. The crystal structure can be described as a stacking of distorted c. p. 36 chalcogen layers and mixed square 44 alkali‐chalcogen layers.  相似文献   

19.
The crystal structure of RbH3(SeO3)2 has been determined from three-dimensional single crystal X-ray diffractometer data obtained at room temperature. Four formula units crystallize in an orthorhombic unit cell of dimensions: a = 5.9192(2), b = 17.9506(5), and c = 6.2519(3) Å. The space group is P212121. The structure consists of two types of chains at a right angle. One chain is built up of H2SeO3 molecules linked by 2.594(8)-Å hydrogen bonds and the other of HSeO3? ions linked by 2.571(12)-Å hydrogen bonds. These two types of chains are cross-linked by a third hydrogen bond of length 2.521(7) Å. The rubidium ion is surrounded by eight oxygen atoms forming a distorted cube. The Rb+O distances are in the range 2.94–3.19 Å.  相似文献   

20.
Nonlinear optical crystals of fluosilicate Na2SiF6 are synthesized via hydrothermal method and its structure is determined by single‐crystal X‐ray diffraction (XRD). The space group of Na2SiF6 is P321 with cell parameters a = 8.8715(3) Å, c = 5.0484(5) Å, Z = 3, V = 344.09(4) Å3. The properties of the crystal are measured by powder XRD, infrared (IR) spectroscopy, ultraviolet/visible (UV/Vis) near‐infrared (NIR) diffuse reflectance spectroscopy, thermogravimetric (TG), and differential scanning calorimetry (DSC) analysis. The bandgap calculated using CASTEP is 7.41 eV, indicating that the cut‐off edge of the Na2SiF6 crystal can be down to deep‐UV energy region. The first‐principles studies were performed to elucidate the structure/property relationship of Na2SiF6.  相似文献   

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