Crystal structures of 6-[(2-hydroxy-1,1-bis-hydroxymethyl-ethylamino)-methylene]-4-nitro-cyclohexa-2,4-dienone hydrate and 6-[(2-hydroxy-1,1-bis-hydroxymethyl-ethylamino)-methylene]-4-bromo-cyclohexa-2,4-dienone

Crystal structures of 6-[(2-hydroxy-1,1-bis-hydroxymethyl-ethylamino)-methylene]-4-nitro-cyclohexa-2,4-dienone hydrate (I) and 6-[(2-hydroxy-1,1-bis-hydroxymethyl-ethylamino)-methylene]-4-bromo-cyclohexa-2,4-dienone (II) have been determined. The crystals of I are monoclinic, a = 16.957(1) Å, b = 10.729(2) Å, c = 7.240(3) Å; β = 99.56(3)°, space group P2₁/c, Z = 4, R = 0.0492. The crystals of II are triclinic, a = 10.282(2) Å, b = 7.189(3) Å, c = 16.831(3) Å; α = 90.67(3)°, β = 100.10(3)°, γ = 95.87(3)°; space group P-1, Z = 4, R = 0.0591. The independent part of the unit cell of I contains one unique molecule and water of crystallization, while in II — two unique molecules A and B. C(CH₂OH)₃ fragment of the molecule B manifests the disordering of alcohol oxygen atoms. Both in I and II, the salicylidene fragment of the molecules exists in the quinoid tautomeric form.     

Crystal structures of condensation products of 3,5-dibromosalicylic aldehyde with streptocide, norsulfazole, and ethazole

Crystal structures of 4-[(3,5-dibromo-2-hydroxy-benzylidene)-amino]-benzenesulfonamide (I), 4-[(3,5-dibromo-2-hydroxy-benzylidene)-amino]-N-thiazol-2-yl-benzenesulfonamide (II), and 4-[((3,5-dibromo-2-hydroxy-benzylidene)-amino]-N-(5-ethyl-1,3,4-thiadiazol-2-yl)-benzenesulfonamide (III) have been determined. The crystals of I are monoclinic, a = 8.645(2) Å, b = 12.622(3) Å, c = 14.414(3) Å; β = 104.31(3)°, space group P2₁/n, Z = 4, R = 0.0642. The crystals of II are also monoclinic, a = 10.313(2) Å, b = 11.288(2) Å, c = 15.766(3) Å; α = 99.37(3)°, space group P2₁/c, Z = 4, R = 0.0635. The crystals of III are triclinic, a = 10.567(2) Å, b = 10.849(2) Å, c = 18.432(4) Å; α = 75.97(3)°, β = 89.71(3)°, γ = 87.33(3)°, space group P-1, Z = 4, R = 0.0644. The asymmetric part of the unit cell of compounds I and II contains a single molecule of the Schiff’s base, while in III two independent azomethine molecules A and B. The studied compounds I–III adopt the E-configuration relatively to the double azomethine bond C=N. Owing to phenolic oxygen together with nitrogen and oxygen atoms of the sulfonamide group, compound I makes in a crystalline state a two-dimensional hydrogen bonded network parallel to the plane (1 0 1). Compound II forms centrosymmetric dimers in the crystals via N-H…N hydrogen bonds. These dimers, in their turn, are connected by hydrogen bonds O-H…O into infinite chains running along the double screw axis b. As in II, molecules and of compound III form centrosymmetric dimers through hydrogen bonding N-H…N. These dimers are linked into infinite chains running along the c axis by hydrogen bonds C-H…O. The π-π-stacking interaction of aromatic rings is observed in all the compounds studied.     

Die kristall- und molekúlstruktur der dimeren dimethylaluminium- und dimethylgallium-N,N′-dimethylacetamidine [(CH3)2M(NCH3)2CCH3]2 (M = Al,Ga)

Dimethylaluminium- and dimethylgallium-N,N′-dimethylacetamidine (I and II) are doubly associated forming a puckered eight-membered ring. They crystallize isostructurally in the monoclinic space group P2₁/c with two dimers per unit cell. The lattice constants of I are a 8.187, b 7.266, c 14.778 Å, β 103.58° and those of II a 8.163, b 7.277, c 14.835 Å, β 103.46°. The MN and the NC bond lengths within the rings are nearly equal, their mean values are for I: AlN 1.925 Å, CN 1.330 Å and for II: GaN 1.979 Å, CN 1.335 Å. This is also true for the exocyclic bond lengths with average values AlC 1.975 Å, NC 1.474 Å, CC 1.509 Å (for I) and GaC 1.998 Å, NC 1.484 Å and CC 1.507 Å (for II). The metal atoms are tetrahedrally coordinated, and the distortion is only slight. The final R-values are 0.034 and 0.056, respectively.     

Crystal structure of the pyrovanadate K4V2O7

The crystal structure of anhydrous K₄V₂O₇ (I) is determined by powder X-ray diffraction. The compound crystallizes in the monoclinic system (a = 10.222(1) Å, b = 6.2309(8) Å, c = 7.282(1) Å, β = 101.31(1)°, space group C2/m, Z = 2). The structure contains layers of isolated V₂O₇ pyrovanadate groups separated by layers of potassium cations. The hydration and dehydration of I are studied by thermal analysis and high-temperature X-ray diffraction. The dehydration is accompanied by decomposition of the starting crystal hydrate to give intermediate compounds. Anhydrous compound I undergoes a reversible phase transition at 740°C. The high-temperature phase is assumed to have a hexagonal unit cell (a = 6.169(4) Å, c = 15.72(1) Å, Z = 2).     

Synthesis and crystal structure of two derivatives of benzodiazepines

Two benzodiazepine derivatives, C₂₃H₂₂N₂O (I), 2-methyl-8-methoxy-2,4-diphenyl-2,3-dihydro-1H-1,5-benzodiazepine, and C₂₂H₁₇N₃O₂Br₂ (II), 2-methyl-7-nitro-2,4-bis(4′-bromophenyl)-2,3-dihydro-1H-1,5-benzodiazepine, were studied by single crystal X-ray diffraction method. Compound (I) crystallizes in the monoclinic system, space group P2₁/c, a = 13.1703(17) Å, b = 11.1990(14) Å, c = 12.9093(16) Å, β = 107.831(2)°, V = 1812.6(3) ų, Z = 4. Compound (II) crystallizes in the monoclinic system, space group P2₁/n, a = 11.7345(12) Å, b = 12.7477(13) Å, c = 13.5965(14) Å, β = 95.221(2)°, V = 2025.4(4) ų, Z = 4. The molecules of (I) and (II) have T-shape form with the diazepine ring at the junction point. The seven membered central benzodiazepine ring in both structures adopt a twist-boat conformation. The crystal packing is stabilized by C-H…π (in I) and C-H…O (in II) interactions.     

Crystal growth and X-ray data of the lead phosphates Pb4P2O9 and Pb8P2O13

Single crystals of the title compounds have been grown by the Czochralski technique. Pb₄P₂O₉ crystallizes in the space group $\text{P2}{}_1\text{c}$ with the parameters a = 9.4812 Å, b = 7.1303 Å, c = 14.390 Å, β = 104.51° and Pb₈P₂O₁₃ in $\text{C2}\text{m}$ with a = 10.641 Å, b = 10.206Å c = 14.342 Å, β = 98.34°.     

The crystal structures of the 1-methyl-3,4-benzo-1-telluracyclopentane and 1-phenyl-1-telluracyclopentane cations in their tetraphenylborate salts,C8H8TeMe+ BPh4− and C4H8TePh+ BPh4−

The crystal structures of C₈H₈TeMe⁺ BPh₄^? (I) and C₄H₈TePh⁺ BPh₄^? (II) have been determined from three-dimensional X-ray counter data.I is monoclinic, space group P2₁/n with a 9.175(1), b 17.402(3), c 16.998(3) Å, β 98.92(6)°, Z = 4, R = 5.1% for 1641 observed reflections.II is triclinic, space group P$\text{1}$ with a 9.635(3), b 17.721(3), c 16.858(8) Å, α 89.77(2), β 104.36(4), γ 90.16(2)°, Z = 4, R = 9.0% for 6466 observed reflections.In both I and II tellurium is three-coordinate in a pyramidal geometry, with TeC distances in the range 2.07(1)–2.14(1) Å (I) and 2.10(1)–2.17(1) Å (II). In both structures short contacts of 3.4—3.5 Å occur between tellurium and carbon atoms of the tetraphenylborate anion.     

Crystal structures of pyridine-4-aldehyde thiosemicarbazone perchlorate and trifluoromethane sulfonate

The new salts of pyridine-4-aldehyde thiosemicarbazone: perchlorate (I) and trifluoromethane sulfonate (II) HN⁺C₅H₄-CH=N-NH-C(S)-NH₂·X^? (X = ClO₄, CF₃SO₃) were synthesized and studied by IR and NMR spectroscopy and X-ray diffraction analysis. The compounds were synthesized by a reaction of pyridine-4-aldehyde thiosemicarbazone with chloric or trifluoromethane sulfonic acid, respectively. Compound I crystallized in the triclinic crystal system, space group P-1, a = 6.8691(2) Å, b = 9.5406(4) Å, c = 9.6348(4) Å, α = 78.838(1)°, β = 77.618(1)°, γ = 69.661(1)°, Z = 2. Compound II crystallized in the monoclinic crystal system, space group P2₁/c, a = 7.3149(8) Å, b = 11.9830(16) Å, c = 15.143(2) Å, β= 96.949(4)°, Z = 4. The structures are formed by hydrogen-bonded ions. Moreover, the cations are linked in “dimmers” due to the weak N-H...S hydrogen bonds.     

X-ray and mössbauer studies of tricyclohexyltin(IV) halides. The crystal structures of (cyclo-C6H11)3SnX (X = F,Br and I)

The structures of tricyclohexyltin fluoride (I), bromide (II) and iodide (III) have been determined by X-ray analysis. Compound I crystallizes in the space group P2₁/m with a = 10.422(6), b = 17.238(9), c = 5.769(3) Å, β = 104.6(1)° and Z = 2. Compounds II and III crystallize in the space group Pcmn with a = 10.427(6), b = 16.914(9), c = 11.366(6) Å, Z = 4; and a = 10.400(6), b = 16.900(10), c = 11.400(4) Å, Z = 4, respectively. All three structures consist of discrete tetrahedral (cyclo-C₆H₁₁)₃SnX units.The temperature dependence of the Mössbauer resonance areas has been examined in order to obtain information about the relationship between chemical structure and lattice dynamics.     

Structure and properties of heterocomplex compounds based on lead(II) hexafluoroacetylacetonate and copper(II) β-diketonates

Single crystal X-ray diffraction study has been performed for heterometallic complexes based on lead(II) hexafluoroacetylacetonate and copper(II) β-diketonates. Crystal data for Cu(aa)₂·Pb(hfa)₂: a = 8.741(2) Å, b = 12.124(2) Å, c = 13.741(3) Å, α = 89.70(3)°, β = 89.50(3)°, γ = 75.06(3)°, space group P-1, Z = 2, d _calc = 2.084 g/cm³; for Cu(hfa)₂ Pb(hfa)₂: a = 9.334(2) Å, b = 14.584(3) Å, c = 23.102(5) Å, β = 96.82(3)°, space group P2₁/c, Z = 4, d _calc = 2.338 g/cm³. It is demonstrated that the principal structural motif for these compounds is a chain coordination polymer, which consists of alternating molecules of the complexes. The results of a thermogravimetric study for the compounds are reported.     

The crystal and molecular structure of the tetraethylammonium salt of tetrahydridopentadecacarbonyltetrarhenate(2−) in two crystallographic forms

The structure of the title compound, (NEt₄)₂[H₄Re₄(CO)₁₅], is reported in two crystallographic modifications, I and II. Both forms axe monoclinic and the cell constants are as follows: I, a 11.355(2), b 21.204(4), c 17.416(3) Å, β 94.15(2)°, space group P2₁/c; II, a 21.831(4), b 17.584(3), c 11.446(2) Å, β 96.02(2)°, space group P2₁,/n. Two sets of 3042 (I) and 2870 (II) independent diffraction intensities, collected by counter methods, were used for the solution and refinement of the two structures. The final conventional R factors have values 5.5% (I) and 6.3% (II), respectively. The crystal packings are compared, showing different conformations of the (NEt₄)⁺ cations. The anions contain a tetrametal cluster formed by an isosceles triangle plus an apically bound metal atom; the carbonyl groups are all terminally bonded to the rhenium atoms. Some differences, present both in the metal atom clusters and in the carbonyl dispositions, are discussed and compared with a third, previously reported, crystallographic modification of the same compound.     

Synthesis and crystal structure of {(2-α-pyridylethyl)tris(phenyl)phosphonium}trichlorozinc(II)

The structure of the complex {(2-α-pyridylethyl)tris(phenyl)phosphonium}trichlorozinc(II), which is an unexpected product of the reaction of the Zn²⁺ ion with coordinated 4,5-(2-pyridylethylene)dithio-1,3-dithiol-2-thione, is described. The reaction mechanism is studied by the ESI method of positive and negative ions. The crystals are monoclinic, space group P2₁/c, a= 16.129(3) Å, b = 11.167(2) Å, c = 14.874(3) Å β = 91.77(3)°, Z = 4. The Zn(II) atom has a quasi-tetrahedral environment of three chloride ions and one phosphonium cation coordinated at the nitrogen atom of the pyridyl fragment.     

Metal-silicon bonded compounds : X. The molecular structures of 2,2,4,4,6,6,8,8-octamethyl-2,4,6,8-tetrasila-1,5-mercuracyclooctane and bis(triphenylsilyl) mercury

The crystal and molecular structure determinations of 2,2,4,4,6,6,8,8-octamethyl-2,4,6,8-tetrasila-1,5-mercuracyclooctane. Hg₂Si₄C₁₀H₂₈ (I) and of bis-(triphenylsilyl)mercury, (Ph₃Si)₂Hg (II), are reported. The structures have been determined from single-crystal X-ray data collected by counter methods. Both molecules crystalize in the space group P1 with one centrosymmetric molecule per unit cell. Each structure contains linear SiHgSi groups, with mercury-silicon distances of 2.490(4) Å in I and 2.503(4) Å II. In compound I the SiHgSi groups are linked by methylene bridges which form an eight member ring in the chair conformation. The cell dimensions for compound I are a 6.277(2), b 8.408(2), c 9.274(4) Å, α 92.75(3), β 94.79(3) and γ 100.14(2)° with R₁0.062 for 1809 observed reflections. The cell dimensions for compound II are a 9.999(4), b 11.727(8), c 7.654(5) Å, α 99.87(5), β 115.35(4) and γ 98.41(4)°, with R₁0.081 for 2394 observed reflections.     

Crystal structure of diacetato-bis(2-methyl-2-propylamine)zinc(II)

The diacetato-bis(2-methyl-2-propylamine)zinc(II) compound crystallizes in the triclinic system, space group P-1 with unit cell parameters a = 10.0144(10)Å, b = 10.2687(10)Å, c = 10.5149(10)Å. α = 115.184(2)°, β = 97.489(2)°, γ = 114.066(2)°, ν = 830.85(14)ų. The obtained solid state structure of (^tBuNH₂)₂Zn(OOCCH₃)₂ shows both inter- and intramolecular NH—O hydrogen bond interactions which are analyzed.     

High-pressure syntheses of TaS3, NbS3, TaSe3, and NbSe3 with NbSe3-type crystal structure

Transition metal trichalcogenides TaSe₃, TaS₃, NbSe₃ and NbS₃ were prepared under the reaction conditions of 2 GPa, 700°C, 30 min. NbSe₃ is exactly the same as that obtained in the usual sealed-tube method. The other products are modifications of each usual phase. They have crystal structures very similar to that of NbSe₃. The lattice parameters are a = 10.02Å, b = 3.48 Å, c = 15.56 Å, β = 109.6° for TaSe₃, a = 9.52 Å, b = 3.35 Å, c = 14.92 Å, β = 110.0° for TaS₃, and a = 9.68 Å, b = 3.37 Å, c = 14.83 Å, β = 109.9° for NbS₃. In spite of the similarity in their crystal structures, these high-pressure phases show a variety of electrical transport properties. TaSe₃ is a superconductor having T_c at 1.9 K. TaS₃ is a semiconductor with two transitions at 200 and 250 K. NbS₃ is a semiconductor with E_a = 180 MeV.     

Crystal structures of 2-ferrocenylmethylidenehydrazono-1,3-dithiane and 2-ferrocenylmethylidenehydrazono-1,3-dithiepane

Two compounds of 2-ferrocenylmethylidenehydrazono-1,3-dithiane (1) and 2-ferrocenylmethylidenehydrazono-1,3-dithiepane (2) are synthesized and their single crystal structures are determined by the X-ray diffraction method. Compound 1 belongs to the orthorhombic Pca2₁ space group with the cell parameters: a = 13.989(4) Å, b = 5.785(2) Å, c = 18.231(5) Å, V = 1475.4(7) ų; while compound 2 crystallizes in a monoclinic symmetry, P2₁/c space group with a = 15.320(2) Å, b = 5.8028(6) Å, c = 36.584(4) Å, β = 91.932(1)° and V = 3250.4(6) ų.     

A phase-analytical study of the TlCuSe system

High-temperature silica-tube syntheses and room-temperature copper extraction experiments of the single phases found with the former technique have established five new ternary phases in the TlCuSe system. The compositions were determined by microprobe analysis. The new phases have been crystallographically characterized by means of single-crystal and powder diffraction: TlCu₃Se₂ (CsAg₃S₂ type),a = 15.2128(7)Å,b = 4.0115(2)Å,c = 8.3944(4)Å, β = 111.700°(4); Tl₅Cu₁₄Se₁₀ (new type),C2/m?)a = 18.097(2)Å,b = 3.9582(2)Å,c = 18.118(2)Å, β = 116.089°(7); TlCu₅Se₃ (new type,P4¯n2?),a = 12.9023(2)Å,c = 3.9905(1)Å; TlCu_5−xSe₃ (new type,Pnn2?),a = 12.43(1)Å,b = 12.80(1)Å,c = 3.93(1)Å; TlCu₇Se₄ (NH₄Cu₇S₄ type),a = 10.4524(2)Å,c = 3.9736(1)Å. The latter phase may be considered as stoichiometric crookesite.     

New SbS2 strings in the BaSb2S4 structure

The new compound BaSb₂S₄ crystallizes in the monoclinic system (space group: $\text{P2}{}_1\text{c}$, No. 14) with a = 8.985(2) Å, b = 8.203(3) Å, c = 20.602(5) Å, β = 101.36(3)°. SbS₃ ψ tetrahedra and ψ-trigonal SbS₄ bipyramids are connected by common corners and edgers to infinite strings. These are arraged cross-wise in sheets perpendicular to the c axis.     

Ternary chalcogenide compounds AB2X4: The crystal structures of SiPb2S4 and SiPb2Se4

The crystal structures of SiPb₂S₄ and SiPb₂Se₄ were determined from three dimensional X-ray diffraction data collected with Mo radiation. Both structures are monoclinic with space group $\text{P2}{}_1\text{c}$ and 4 formula units per unit cell. Lattice dimensions for SiPb₂S₄ are a = 6.4721(5) Å, b = 6.6344(9) Å, c = 16.832(1) Å, and β = 108.805(7)°. For SiPb₂Se₄, a = 8.5670(2) Å, b = 7.0745(3) Å, c = 13.6160(3) Å, and β = 108.355(3)°. The Si is tetrahedrally coordinated to S and Se with SiS about 2.10 Å and SiSe about 2.27 Å. The structural framework can be described as consisting of trigonal prisms of S or Se atoms which form a prismatic tube by sharing the triangular faces. These tubes in turn share edges to form corrugated sheets, with the unshared edges projecting alternately on each side of the sheet. The structures are very similar but not identical. In the sulfide one Pb is in sevenfold coordination and the other crystallographically independent Pb is in eightfold coordination. The PbS distances range from 2.82–3.50 Å. In SiPb₂Se₄ both Pb atoms are in sevenfold coordination. PbSe distances range from 2.97 to 3.54 Å. In the sulfide the Pb atoms form a zig-zag chain within the channels formed by the prismatic tubes while in the selenide they are in a straight line.     

The crystal structure of bisphenoxatelluronium dinitrate,C24H16O9N2Te2

Bisphenoxatelluronium dinitrate is monoelinie, P2₁/c: a = 11.638(4), b = 28.266(8), c = 8.546(3) å, β = 119.73(2)°, z = 4 at t = 22°. All atoms including hydrogen were located. The two ring systems, I and II, are folded along their Te-O axes, 147° and 163°, respectively. The average ring bond distances are: Te-C = 2.091, C-C = 1.377, C-O = 1.370 Å. Each Te is bonded to one NO₃ group, Te1-ON1 = 2.485(5), Te2-ON4 = 2.393(4) Å, and an oxygen bridge connects the ring systems, Te1-OB = 1.966(4), Te2-OB = 2.001(4) Å, Te1-OB-Te2 = 125.0(2)°. The bond distances and angles of the structure are compared to those of related compounds.