The Effect of Solvent on Isomer Formation. Synthesis and Crystal Structures of CdII Complexes with 3-Nitrobenzoate and Thiourea

2002 ◽  
Vol 55 (9) ◽  
pp. 611 ◽  
Author(s):  
S.-L. Zheng ◽  
W. Li ◽  
G. Yang ◽  
X.-M. Chen ◽  
H.-G. Zhu ◽  
...  
Keyword(s):  
Solvent Effect ◽  
Crystal Structures ◽  
The Other ◽  
Orthorhombic Space Group ◽  
Triclinic Space Group ◽  
Crystal Forms ◽  
Space Group ◽  
Water Solutions ◽  
Effect Of Solvent ◽  
Carboxylate Shift

Two crystal forms of bis(3-nitrobenzoato)bis(thiourea)cadmium(II) were obtained by the reaction of Cd(NO3)2�4H2O, 3-nitrobenzoate (mNA) and thiourea (TU) from ethanol and water solutions, respectively. One is cube-shaped and crystallizes in the orthorhombic space group Pbca and consists of discrete mononuclear molecules of bis(3-nitrobenzoato-O,O�)bis(thiourea)cadmium(II) (1). The other form is needle shaped and crystallizes in the triclinic space group P1–.It is comprised of discrete molecules of bis(3-nitrobenzoato-O,O�)bis(thiourea)cadmium(II) (2) and (3-nitrobenzoato-O,O�)(3-nitrobenzoato-O)bis(thiourea)cadmium(II) (3). (1), (2) and (3) are isomers, in which (1) may be regarded as a structural intermediate between (2) and (3) in the 'carboxylate shift' process. The formation of these isomers may be influenced by the solvent effect.

Kristallstrukturen der iodierten closo-Hexaborate trans-(Ph4P)2[B6H4I2], mer-(Ph4P)2[B6H3I3] · 2 CH2Cl2, trans-(Ph4P)2[B6H2I4] · 2 CH3CN und (CH2Py2)[B6HI5]/Crystal Structures of the Iodized closo-Hexaborates trans-(Ph4P)2[B6H4I2], mer-(Ph4P)2[B6H3I3] · 2 CH2Cl2, trans-(Ph4P )2[B6H2I4] · 2 CH3CN and (CH2Py2)[B6HI5]

1998 ◽  
Vol 53 (2) ◽  
pp. 206-210 ◽  
Author(s):  
D. Sonnak ◽  
W. Preetz
Keyword(s):  
Single Crystals ◽  
Crystal Structures ◽  
Monoclinic Space Group ◽  
Orthorhombic Space Group ◽  
Triclinic Space Group ◽  
Space Group ◽  
X Ray ◽  
Structure Determinations

Abstract X-ray structure determinations have been performed on single crystals of trans-(Ph4P)2-[B6H4I2] (1) (triclinic, space group P1̄, a = 9.9680(12), b = 10.9690(11), c = 11.0470(14) Å,α = 88.167(9), β = 80.466(12), γ = 68.839(11)°, Z = 1), mer-(Ph4P)2[B6H3I3] · 2 CH2Cl2 (2)(triclinic, space group P1̄, a = 11.8694(11), b = 15.1699(13), c = 17.051(2) Å, α = 75.118(9), β = 71.953(10), γ = 69.331(8)°, Z = 2), trans-(Ph4P )2[B6H2I4] · 2 CH3CN (3) (monoclinic, space group P21/n, a = 14.9665(10), b = 7.6783(10), c = 23.385(3) Å, β = 95.78(9)°, Z = 2), and (CH2Py2)[B6HI5] (4) (orthorhombic, space group Pnma, a = 13.660(2), b = 11.8711(13), c = 13.839(2) Å, Z = 4). The B6 octahedra are compressed in the direction of the B-I bonds, resulting in shortened diagonal B ··· B distances with average values of the groups I-B ··· B-I = 2.37 and I-B ··· B-H = 2.43 Å as compared with H-B ··· B-H = 2.49 Å.

Synthese und Kristallstruktur der (p-Brombenzyl)triphenylphosphonium-bromide: [(p-Br-C6H4-CH2)P(C6H5)3]+B-;[(p-Br-C6H4-CH2)P(C6H5)3]+Br2- und [(p-Br-C6H4-CH2)P(C6H5)3]+Br3-/ Synthesis and Crystal Structures of (p-Bromobenzyl)triphenylphosphonium Bromides, [(p-Br-C6H4-CH2)P(C6H5)3]+Br-;[(p-Br-C6H4-CH2)P(C6H5)3]+Br- and [(p-Br-C6H4-CH2)P(C6H5)3]+Br3-

1996 ◽  
Vol 51 (10) ◽  
pp. 1443-1448 ◽  
Author(s):  
H. Vogt ◽  
D. Wulff-Molder ◽  
M. Meisel
Keyword(s):  
Crystal Structures ◽  
Weak Interactions ◽  
Orthorhombic Space Group ◽  
Tetrahedral Geometry ◽  
Chlorine Atoms ◽  
Triclinic Space Group ◽  
Space Group ◽  
Triphenylphosphonium Bromide

(p-Bromobenzyl)triphenylphosphonium Bromide, [(p-Br-C6H4-CH2)P(C6H5)3]+Br- · (CH2Cl2)2.5 (1) has been prepared by the reaction of triphenylphosphine with p-bromobenzylbromide and its structure determined (triclinic, space group P1̅, Z = 2, a = 1198.03(12), b = 1245.80(11), c = 1258.42(12)pm, a = 100.170(8), β = 103.543(9), γ = 1 18.158(7)°. The compound exists as Br- anions and [(p-Br-C6H4- CH2)P(C2H5)3]+ cations, with weak interactions between the chlorine atoms of the CH2Cl2 molecules and the bromine bonded in the cation. [p-Br-C6H4-CH2)P(C6H5)3]Br2 (2) and [(p-Br-C6H4-CH2)P(C6H5)3]Br3·(CH2Cl2)1.5 (3) have been obtained by reactions of the corresponding amounts of bromine with 1 in methylenechloride solution. The yellow-red crystals of 2 are orthorhombic, space group Pccn, Z = 8, a = 2060.8(3), b = 1223.6(4), c = 1860.8(3) pm. Compound 2 exists as [p-Br-C6H4-CH2)P(C6HO5)3]+ cations and linear Br2-4 units with a bromide-bromine distance of 297.3(4) pm. The red crystals of (3) are triclinic, space group P1̅, Z = 2, a = 1 171.16(7), b = 1260.97(8), c = 1270.35(7)pm, α = 65.510(5), β = 75.811(5), γ = 62.320(5)°, and contain [(p-Br-C6H4-CH2)P(C6H5)3]+ cations and linear, slightly asymmetrical Br-3 anions. In all cases the cation has a slightly irregular tetrahedral geometry around the P atom.

Growth ordering and anomalous birefringence in ugrandite garnets

2005 ◽  
Vol 69 (4) ◽  
pp. 537-550 ◽  
Author(s):  
A. G. Shtukenberg ◽  
D. Yu. Popov ◽  
Yu. O. Punin
Keyword(s):  
Crystal Structures ◽  
Dipole Approximation ◽  
Partial Ordering ◽  
Point Dipole ◽  
Orthorhombic Space Group ◽  
Orthorhombic Crystal ◽  
Triclinic Space Group ◽  
Space Group ◽  
Point Dipole Approximation ◽  
Octahedral Cations

AbstractIntermediate members of the grossular–andradite and grossular–uvarovite series are known to display anomalous birefringence, which is inconsistent with the ideal cubic space group of garnet Ia3̄d. To determine the reason for such birefringence, the crystal structures of at least 15 samples were refined by different authors including the present ones. The crystals with the value of anomalous birefringence of Δn > 0.001 are normally characterized by partial ordering of the octahedral cations (Al/Fe and Al/Cr for grossular–andradite and grossular–uvarovite series, respectively). This reduces the symmetry to the orthorhombic space group Fddd or even to the triclinic space group I1̄. As is seen from the distribution of occupancies over octahedral sites in the triclinic space group, eight occupancies are grouped into two quartets of similar occupancies, leading to pseudo-orthorhombic crystal structures. The variety of structures with different degrees of pseudo-orthorhombicity is due to the action of the growth dissymmetrization mechanism. Simulations of the optical indicatrix in the point-dipole approximation confirm cation ordering as the main cause of the anomalous birefringence.

Tetrakis(tetrahydrofuran-O)calcium- und -strontium-bis[bis(trimethylsilyl)-arsanid] - Vergleich der spektroskopischen Parameter sowie der Molekülstrukturen / Tetrakis(tetrahydrofuran-O)calcium and strontium Bis[bis(trimethylsilyl)-arsanide] - A Comparison of the Spectroscopic Parameters and the Molecular Structures

1995 ◽  
Vol 50 (1) ◽  
pp. 106-114 ◽  
Author(s):  
Matthias Westerhausen ◽  
Wolfgang Schwarz
Keyword(s):  
Bond Length ◽  
Molecular Structures ◽  
The Other ◽  
Trans Isomers ◽  
Orthorhombic Space Group ◽  
Triclinic Space Group ◽  
Spectroscopic Parameters ◽  
Space Group

Calcium- and strontium bis[bis(trimethylsilyl)amide] react with bis(trimethylsilyl)arsane in tetrahydrofuran to give the corresponding tetrakis(tetrahydrofuran-O) metal bis[bis(trimethylsilyl)arsanides]. The calcium derivative crystallizes in the triclinic space group P1̄ with a = 1191.7(2), b = 1232.0(2), c = 1655.0(2) pm, α = 102.46(1)°, β = 107.92(1)°, γ = 104.66(1)° and Ζ = 2, the strontium derivative in the orthorhombic space group Pbca with a = 2153.4(3), b = 1852.2(3), c = 2182.4(3) pm and Z = 8. Both molecules exist as trans-isomers with a nearly linear As-M-As moiety; however, the strontium analogue contains two remarkably different configurations for the arsenic atoms. One As atom is surrounded nearly trigonally planar with a Sr-As bond length of 310 pm, whereas the other pnictogen atom has an angle sum of 338° with a Sr-As distance of 315 pm.

Structures of 2,6-disubstituted naphthalenes

1999 ◽  
Vol 55 (1) ◽  
pp. 85-94 ◽  
Author(s):  
James A. Kaduk ◽  
Joseph T. Golab
Keyword(s):  
Crystal Structures ◽  
Ester Group ◽  
Carboxyl Groups ◽  
Monoclinic Space Group ◽  
Ring Plane ◽  
Orthorhombic Space Group ◽  
Triclinic Space Group ◽  
Space Group ◽  
X Ray ◽  
The Mean

The crystal structures of 2,6-naphthalenedicarboxylic acid (NDA) and dimethyl 2,6-naphthalenedicarboxylate (NDC) have been solved ab initio using a combination of X-ray powder diffraction and computational chemistry techniques. These two crystal structures, and that of 2,6-dimethylnaphthalene (DMN), have been refined by the Rietveld technique. DMN crystallizes in the orthorhombic space group Pbca, with a = 7.4544 (4), b = 6.0826 (6), c = 20.0946 (12) Å, V = 911.1 (1) Å3 and Z = 4. The structure consists of a herringbone stacking parallel to a, resulting in loosely bound layers perpendicular to c. NDA crystallizes in the triclinic space group P1¯, with a = 3.7061 (8), b = 7.4688 (14), c = 8.5352 (22) Å, α = 86.62 (2), β = 85.49 (2), γ = 87.99 (2)°, V = 235.00 (6) Å3 and Z = 1. The structure consists of loosely packed hydrogen-bonded chains along [11¯1]. NDC crystallizes in the monoclinic space group P21/c, with a = 13.41931 (14), b = 6.14869 (5), c = 7.15257 (5) Å, β = 100.400 (1)°, V = 580.47 (1) Å3 at 300 K and Z = 2. The structure consists of layers of NDC molecules perpendicular to a. The ester group is twisted 20° out of the mean ring plane in NDC. The conformations of the carboxyl groups in NDA and NDC differ. MP2 calculations suggest that the observed twist in NDC corresponds to an increase in conformational energy of 9 kJ mol−1.

scholarly journals Organic and inorganic templates bearing CCo3(CO)9 cluster fragments: X-ray crystal structures of C(CH2OCOCCl3)4 and of CH3C(O)CHC(OH)MLn where MLn = CCo3(CO)9 or (C6H5)Cr(CO)3

1995 ◽  
Vol 73 (7) ◽  
pp. 1196-1205 ◽  
Author(s):  
Lisa C.F. Chao ◽  
Andreas Decken ◽  
James F. Britten ◽  
Michael J. McGlinchey
Keyword(s):  
Molecular Weight ◽  
Crystal Structures ◽  
Cluster Complex ◽  
Molecular Crowding ◽  
Space Filling ◽  
Orthorhombic Space Group ◽  
Triclinic Space Group ◽  
Space Group ◽  
X Ray ◽  
Molecular Weight Product

Pentaerythritol and trichloroacetyl chloride react to yield the tetrakis-trichloroacetate ester C(CH2-O2C-CCl3)4, 5, which crystallizes in the triclinic space group [Formula: see text] with a = 9.874(2) Å, b = 11.811(2) Å, c = 12.858(3) Å, α = 114.35(3)°, β = 95.63(3)°, γ = 99.11 (3)°, and V = 1326.5(5) Å3 for Z = 2. The molecule adopts a geometry in which the trichloroacetate chains fold to produce a flattened tetrahedron, giving a molecule of approximate D2d symmetry. Treatment of 5 with CO2(CO)8 gave, as the highest molecular weight product, the tris-cluster complex C[CH2-O2C-CCo3(CO)9]3(CH2-O2C-CCl3), 6, rather than the tetra-cluster C[CH2-O2C-CCo3(CO)9]4, 7. A space-filling model of 7, derived by replacing the CCl3 groups in 5 by CCo3(CO)9 moieties, exhibited considerable molecular crowding. Reaction of several 1,1,1-trichloroacetylacetonate salts with Co2(CO)8 gave the corresponding cluster complexes of Co(II), Co(III), or Al(III). The uncomplexed cluster ligand CH3C(O)CHC(OH)CCo3(CO)9, 9, crystallizes in the orthorhombic space group Pna21 with a = 16.226(2) Å, b = 11.6300(10) Å, c = 9.919(2) Å, V = 1871.7(4) Å3 for Z = 4. The direction of enolization of 9 has been studied by EHMO calculations. The tendency to enolize is also found in (benzoylacetone)Cr(CO)3, 17, which crystallizes in the tetragonal space group P43212 with a = 10.0840(10) Å, b = 10.0840(10) Å, c = 25.387(5) Å, V = 2581.5(6) Å3 for Z = 8. Keywords: inorganometallic clusters.

Kristallstrukturen und Normalkoordinatenanalyse von trans-(n-Bu4N)2 [ReCl4IX], X = NCS, NCSe / Crystal Structures and Normal Coordinate Analyses of trans-(n-Bu4 N)2[ReCl4 IX], X = NCS, NCSe

1999 ◽  
Vol 54 (6) ◽  
pp. 767-771 ◽  
Author(s):  
L. Homolya ◽  
S. Strueß ◽  
W. Preetz
Keyword(s):  
Low Temperature ◽  
Diffraction Analysis ◽  
Crystal Structures ◽  
X Ray Diffraction ◽  
Normal Coordinate ◽  
Orthorhombic Space Group ◽  
Triclinic Space Group ◽  
Space Group ◽  
X Ray ◽  
Ir And Raman

The crystal structures of trans-(n-Bu4N)2[ReCl4I(NCS)] (triclinic, space group P1, a = 11.268(3), b = 11.696(2), c = 18.109(3) A, a = 98.68(2) β = 106.40(2), γ= 97.58(2)°, Z = 2)and trans-(n-Bu4N)2 [ReCl4I(NCSe)] (orthorhombic, space group P212121 a = 11.839(2), b = 12.2679( 10), c = 31.136(5) A, Z = 4) have been determined by single crystal X-ray diffraction analysis. Based on the molecular parameters of the X-ray determinations the low temperature (10 K) IR and Raman spectra o f the (n-Bu4N) salts have been assigned by normal coordinate analysis. The valence force constants are fd(ReN) = 1.69(NCS) and 1.65(NCSe) mdyn/Å

scholarly journals Die Spektren und Kristallstrukturen der Addukte CI5Sb · [N(i-C3H7)CN(i-C3H7)] und Cl4Sn · 2 [N(i-C3H7)CN(i-C3H7)] / Spectra and Crystal Structures of the Adducts Cl5Sb · [N(i-C3H7)CN(i-C3H7)] and Cl4Sn · 2 [N(i-C3H7)CN(i-C3H7)]

1986 ◽  
Vol 41 (10) ◽  
pp. 1223-1229 ◽  
Author(s):  
H.-D. Hausen ◽  
W. Schwarz ◽  
G . Rajca ◽  
J. Weidlein
Keyword(s):  
Crystal Structures ◽  
Vibrational Spectra ◽  
Structure Determination ◽  
Unit Cell ◽  
Molar Ratio ◽  
Orthorhombic Space Group ◽  
Triclinic Space Group ◽  
Space Group ◽  
X Ray ◽  
Ir And Raman

Abstract Spectra and Crystal Structures of the Adducts C l5Sb • [N(/-C3H 7)C N (i-C3H 7)] and C l4Sn • 2 [N(/-C3H 7)CN(/-C3H 7)j X-Ray, Vibrational Data, Diisopropylcarbodiimide Adducts of SbCl5, SnCl4 Thecarbodiimide adducts Cl5Sb <-(—N (R) = C = N R)(1) and Cl4S n ^ (-N (R) = C = N R) 2(2)(R = /-C3H 7) have been prepared by the reaction o f R —N = C —N — R with SbCl5 in a 1:1 and with SnCl4 in a 2:1 molar ratio, respectively. The vibrational spectra (IR and Raman) of both compounds have been regarded and assigned to the skeleton modes. The X-ray structure determination shows the orthorhombic space group Pna2, with 4 formula units per unit cell for 1. Adduct 2 has a trans-configuration and crystallizes in the triclinic space group P 1 with only one molecule per unit cell.

The New Oxometallates Cs4[FeO3], Cs4[ZnO3] and Cs3[BO3] with Trigonal-planar Anions – Decomposition Products of Alkali Metal Suboxometallates

2011 ◽  
Vol 66 (12) ◽  
pp. 1248-1254
Author(s):  
Constantin Hoch
Keyword(s):  
Alkali Metal ◽  
Crystal Structures ◽  
Point Symmetry ◽  
Monoclinic Space Group ◽  
Orthorhombic Space Group ◽  
Decomposition Products ◽  
Triclinic Space Group ◽  
Space Group ◽  
Binary Structure

Three new cesium oxometallates with trigonal-planar [MO3]n− anions (M = Zn, Fe, B) were observed as products of reactions aimed at the formation of alkali metal suboxometallates A9MO4 (A = Rb, Cs; M = Al, Ga, In, Fe, Sc), or as decomposition products thereof. Cs4[FeO3], Cs4[ZnO3] and Cs3[BO3] crystallize with new structure types (Cs4[FeO3]: triclinic, space group P1̄, a = 7.0652(1), b = 7.125(1), c = 9.939(2) Å, α = 80.74(2), β = 71.32(2), γ = 64.04(2)°, Z = 2, Cs4[FeO3]: monoclinic, space group P21/c, a = 7.146(4), b = 18.572(1), c = 7.050(4) Å, β = 115.47(4)◦, Z = 4, Cs3[BO3]: orthorhombic, space group Pnma, a = 10.967(1), b = 10.967(1), c = 10.353(1) Å). In all structures the trigonal-planar anions have no or low point symmetry, but deviate only marginally from ideal 6̄m2 symmetry. The new crystal structures can be derived from simple and highly symmetrical packings of spheres or from known binary structure types.

Structure of buffalo lactoferrin at 2.5 Å resolution using crystals grown at 303 K shows different orientations of the N and C lobes

1999 ◽  
Vol 55 (11) ◽  
pp. 1805-1813 ◽  
Author(s):  
Subramanian Karthikeyan ◽  
Murugan Paramasivam ◽  
Savita Yadav ◽  
Alagiri Srinivasan ◽  
Tej P. Singh
Keyword(s):  
Crystal Structures ◽  
Crystal Form ◽  
Unit Cell ◽  
The Other ◽  
Unit Cell Parameters ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
Cell Parameters ◽  
Other Hand ◽  
External Conditions

The structure of buffalo lactoferrin has been determined at 303 K. The crystals belong to orthorhombic space group P212121, with unit-cell parameters a = 77.5, b = 91.0, c = 131.5 Å and Z = 4. The structure has been refined to an R factor of 0.187. The overall structure of the protein is similar to its structure determined at 277 K in a different crystal form. However, the lobe orientations in the two structures differ by 9.0°, suggesting significant inter-lobe flexibility in this family of proteins. The inter-lobe interactions are predominantly hydrophobic and could act as a cushion for a change in orientation under the influence of external conditions. On the other hand, the domain arrangements are found to be similar in 277 and 303 K crystal structures, with orientations differing by 1.5 and 1.0° in the N and C lobes, respectively. The results of these investigations suggest that the increase in temperature helps in the production of better quality crystals.

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