scholarly journals Solid State Structure of 2,2,4,4,6,6-Hexa(β-naphthyloxo)cyclophosphazatriene and Dipole Moments of Hexa(aryloxo)cyclophosphazatrienes

1989 ◽  
Vol 44 (5) ◽  
pp. 575-581 ◽  
Author(s):  
Giuliano Bandoli ◽  
Umberto Casellato ◽  
Mario Gleria ◽  
Antonio Grassi ◽  
Enzo Montoneri ◽  
...  
Keyword(s):  
Dipole Moment ◽  
Solid State ◽  
Crystal And Molecular Structure ◽  
Dipole Moments ◽  
X Ray ◽  
Substituent Group ◽  
Cell Dimensions ◽  
Unit Cell Dimensions ◽  
Solid State Conformation ◽  
Do So

The crystal and molecular structure of [NP(OC10H7)2]3 was determined by X-ray analysis.The dipole moments of this compound and of the hexa(phenoxo)cyclotriphosphazatrienes of formula [NP(OC6H3XX′Y)2]3 (X = X′ = H, Y = p-Br; X = m-CH3,. X′ = H. Y = p-Cl; X = X′ = m-CH3, Y = p-Cl; X = X′ = m-CH3, Y = H; X = X′ = H, Y = p-CH(CH3)2; X = X′ = H, Y = p-C(CH3)3) were measured in benzene at 25°C. Crystals of [NP(OC10H7)2]3 are monoclinic with unit cell dimensions a = 24.870(15), b = 7.712(8), c = 27.687(14) Å, β = 115.85(7)°; space group P21/c. The structure was refined to an agreement factor of 0.09. The phosphazene ring deviates (max. deviation 17°) from planarity. and mean distances (A) and angles (°) are P-N 1.58(1). P-O 1.58(1), O-C 1.41(2); P-N-P 120(1), N-P-N 119(1), P-O-C 124(2). The conformations of the naphthyloxo groups at P(2) and P(3) are similar, and different from the group at P(1).Dipole moment analysis showed that the solid state conformation changes in the solution state. The measured value was in agreement with a symmetric conformation in which at the O-P-O plane each naphthyloxo group is rotated by ca. 40-50° from the anti-coplanar arrangement relative to this plane. The dipole moment data for the p-substituted phenoxo derivatives agree with such a conformation, but the analysis of the dipole moment values of phosphazenes having phenoxo groups bearing more than one substituent group and p-CH(CH3)2 substituent failed to do so due to the inherent limitations of the method.

The crystal and molecular structure of tris(pentamethylenedithiocarbamate) chromium(III)-chloroform (1 : 2)

1981 ◽  
Vol 46 (1) ◽  
pp. 6-19 ◽  
Author(s):  
Viktor Kettman ◽  
Ján Garaj ◽  
Jaroslav Majer
Keyword(s):  
Molecular Structure ◽  
Structural Analysis ◽  
Crystal And Molecular Structure ◽  
Analysis Method ◽  
Complex Molecules ◽  
Coordination Polyhedra ◽  
X Ray ◽  
Cell Dimensions ◽  
Crustal Density ◽  
Unit Cell Dimensions

The crystal and molecular structure of [Cr(S2CN(CH2)5)3].2 CHCl3 was found by the X-ray structural analysis method. The value R 0.090 was found for 1 131 observed independent reflections. The substance crystallizes in a space group of symmetry P212121 with the following unit cell dimensions: a = 0.8675 (6), b = 1.815(2), c = 2.155(3) nm. The experimentally observed crustal density was 1.48 Mgm-3 and the value calculated for Z = 4 was 1.51 Mgm-3. The CrS6 coordination polyhedron has the shape of a trigonally distorted octahedron, where the D3 symmetry is a approximately retained. The degree of trigonal distortion expressed as the projection of the chelate S-Cr-S angle onto the plane perpendicular to the C3 pseudo axis is Φ = 41.7° (Φ = 60° for an octahedron). The skeleton of the structure formed by the complex molecules contains channels filled with chloroform molecules. The specific type of complex-chloroform interaction consists of the formation of hydrogen bonds of the chloroform protons with the fully occupied pπ-orbitals of the sulphur atoms in the coordination polyhedra. The low stability and crystal decomposition can be explained by loss of chloroform from the channels.

The crystal and molecular structure of tris-butyl-tin(IV)-(1-pyrrolidinecarbodithioato)-3-propionate

1989 ◽  
Vol 54 (3) ◽  
pp. 684-690 ◽  
Author(s):  
Jan Lokaj ◽  
Viktor Vrábel ◽  
Eleonóra Kellö ◽  
Vladimír Ratay
Keyword(s):  
Molecular Structure ◽  
Structural Analysis ◽  
Least Squares ◽  
Least Squares Method ◽  
Crystal And Molecular Structure ◽  
Analysis Method ◽  
Monoclinic System ◽  
X Ray ◽  
Cell Dimensions ◽  
Unit Cell Dimensions

The crystal and molecular structure of Bu3Sn(pyrn-dtc-prop) was solved by the X-ray structural analysis method and refined by the block diagonal least squares method to R = 0.053 for 1 930 observed reflections. The compound crystallizes in the monoclinic system with a space group of P21/c, Z = 4, F(000) = 1 056, with unit cell dimensions of a = 1.4758(5), b = 0.9970(3), c = 1.9166(6) nm; β = 113.90(2)°. The measured and calculated crystal densities were Dm = 1.32 and Dc = 1.31.103 kg m-3. The tin atom is coordinated by three carbon atoms at distances of Sn-C 0.2117(8), 0.2133(8), 0.2158(11) nm and two oxygen atoms O(1) and O(2) at distances of Sn-O 0.2210(5) and 0.2399(5) nm. The coordination polyhedron is a deformed trigonal bipyramid. The S2CN ligand is approximately planar.

Structure and Conformation of Photosynthetic Pigments and Related Compounds, 8 [1]Molecular Structure of an Iron(III) Chlorophyll Derivative-Chloro(phytochlorinato methyl ester)iron(III)

1995 ◽  
Vol 50 (1) ◽  
pp. 139-146 ◽  
Author(s):  
Mathias O. Senge ◽  
Karin Ruhlandt-Senge ◽  
Kevin M. Smith
Keyword(s):  
Molecular Structure ◽  
Crystal And Molecular Structure ◽  
Axial Ligand ◽  
Monoclinic Space Group ◽  
X Ray ◽  
X Ray Crystallography ◽  
Chlorophyll Derivative ◽  
Cell Dimensions ◽  
Unit Cell Dimensions ◽  
Related Compounds

The crystal and molecular structure of chloro(methyl phytochlorinato)iron(III), 4, have been determined by single crystal X-ray crystallography to obtain further information on the conformation of metallochlorins related to chlorophyll. The compound crystallized with two independent molecules mainly distinguished by the orientation of the axial ligand. The macrocycles show significant deviations from planarity larger than those observed in corresponding magnesium(II) complexes. The overall type of distortion is similar to those found in chlorophyllides. Compound 4 crystallized in the monoclinic space group P21 (MoKa,λ = 0.71063 A) with unit cell dimensions a = 12.035(6) Å, b = 13.396(8) Å, c = 19.04(2), b = 97.51(2) Å, Z = 4, V = 3043(4) Å3. The structure was refined to an R-value of 0.075 on the basis of 3974 reflections with I > 3.0σ(Ι) (130 Κ).

scholarly journals Crystal and Molecular Structure of Platinum(II) Complex with Bis(Diphenyl Phosphino)Methane

2019 ◽  
Vol 35 (5) ◽  
pp. 1546-1549
Author(s):  
Karwan Omer Ali ◽  
Hikmat Ali Mohammad ◽  
Thomas Gerber ◽  
Eric Hosten
Keyword(s):  
Crystal And Molecular Structure ◽  
Complex Structure ◽  
Complex Form ◽  
Monoclinic Crystal ◽  
Calculated Density ◽  
X Ray ◽  
X Ray Crystallography ◽  
Square Planar ◽  
Cell Dimensions ◽  
Unit Cell Dimensions

Platinum(II) complex consisting of the tertiarydiphosphine (dppm) ligand had been prepared from PdCl2 with one equiv. of dppm ligand to form [PtC2(dppmCl)] complex where as dppmCl is bis(dipheny1phosphino) chloromethene. Crystal was grown in dichloromethane by slow evaporation process and characterized by X-ray crystallography technic. The complex structure synthesized based upon the identification using X-ray Crystallography and FTIR was [PtC12(dppmCl)], the ligand dppm coordinated to the meta centre as bidentate chelating ligand and form square planar arrangement around Pt(II) metal centre. The bond distances of Pt-P1, Pt-P2, Pt- Cl1 and Pt-Cl2 are 2.217 (2), 2.217 (2), 2.3661 (19) and 2.3661 Aο respectively. The characterized results of Pt(II) complex using X-ray analysis illustrated that [PtC12(dppmCl)] Complex form monoclinic crystal with unit cell dimensions of a = 16.2034(5), b = 7.8274(2), and c = 19.2496 (6) Aο, with β = 98.918 (1)ο, Z=4, calculated density= 1.838 mg/m3, T= 200 k and space group C2/c

Molekül-und Kristallstruktur des 5.5' -Diethoxycarbonyl-3.3' -diethyl-4.4' -dimethyl-pyrromethen-hydrobromids / Crystal and Molecular Structure of 5,5'-Diethoxycarbonyl-3,3'-diethyl-4,4'-dimethyl-pyirromethene Hydrobromide

1978 ◽  
Vol 33 (7) ◽  
pp. 753-755 ◽  
Author(s):  
G. Struckmeier ◽  
J. Engel ◽  
U. Thewalt
Keyword(s):  
Molecular Structure ◽  
Solid State ◽  
Hydrogen Bonds ◽  
Title Compound ◽  
Crystal And Molecular Structure ◽  
Ion Pairs ◽  
Crystal Data ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cell Dimensions

Abstract The crystal and molecular structure of the title compound has been determined by X-ray diffraction. The compound possesses an (almost) planar Z configuration. The ions form ion pairs in the solid state: each bromide anion is connected via two hydrogen bonds with a cation. The crystal data are: space group P21/n with Z = 4; cell dimensions a = 14.097(2), b = 11.591(2), c = 14.133(3) Å, β = 106,22(2)°.

The crystal and molecular structure of the chloro-bis(pentamethylenedithiocarbamate) iron(III)-chloroform (1 : 1) complex

1981 ◽  
Vol 46 (10) ◽  
pp. 2307-2316
Author(s):  
Viktor Kettman ◽  
František Pavelčík ◽  
Jaroslav Majer
Keyword(s):  
Molecular Structure ◽  
Ground State ◽  
Crystal And Molecular Structure ◽  
Analysis Method ◽  
Complex Molecules ◽  
X Ray ◽  
Cell Dimensions ◽  
Unit Cell Dimensions ◽  
Measured Density ◽  
Skeleton Structure

The crystal and molecular structure of FeCl(S2CN(CH2)5)2CHCl3 were solved by the X-ray structural analysis method and refined to R 0.073 for 1996 observed independent reflections. The compound crystallizes in a space group of symmetry P1 with the following unit cell dimensions: a = 0.6384 (5), b = 1.475 (1), c = 1.1966 (6) nm, α = 86.20 (5), β = 95.24 (6), γ = 97.45 (6)°. The experimentally measured density of the crystals of the substance is 1.60 Mgm-3 and the value calculated for Z = 2 is 1.59 Mgm-3. The basic skeleton structure is formed by the complex molecules forms closed cavities filled with chloroform molecules. The central Fe(III) ion is characterized by a quartet ground state (S = 3/2) and is pentacoordinated by a chlorine atom and 4 sulphur atoms in a tetragonal bipyramidal arrangement. The complex-chloroform interaction depends on formation of a double-branched hydrogen bond of the chloroform proton with two sulphur atoms in the coordination polyhedron.

The External Shape of Human γ GI Immunoglobulin from Crystal Sections

1971 ◽  
Vol 29 ◽  
pp. 428-429
Author(s):  
L. W. Labaw
Keyword(s):  
Molecular Weight ◽  
Sodium Phosphate ◽  
Osmium Tetroxide ◽  
Unit Cell ◽  
Monoclinic Space Group ◽  
X Ray ◽  
Large Molecular Weight ◽  
Cell Dimensions ◽  
Unit Cell Dimensions ◽  
Crystallographic Axes

Crystals of a human γGl immunoglobulin have the external morphology of diamond shaped prisms. X-ray studies have shown them to be monoclinic, space group C2, with 2 molecules per unit cell. The unit cell dimensions are a = 194.1, b = 91.7, c = 51.6Å, 8 = 102°. The relatively large molecular weight of 151,000 and these unit cell dimensions made this a promising crystal to study in the EM.Crystals similar to those used in the x-ray studies were fixed at 5°C for three weeks in a solution of mother liquor containing 5 x 10-5M sodium phosphate, pH 7.0, and 0.03% glutaraldehyde. They were postfixed with 1% osmium tetroxide for 15 min. and embedded in Maraglas the usual way. Sections were cut perpendicular to the three crystallographic axes. Such a section cut with its plane perpendicular to the z direction is shown in Fig. 1.This projection of the crystal in the z direction shows periodicities in at least four different directions but these are only seen clearly by sighting obliquely along the micrograph.

Crystallization and preliminary X-ray diffraction studies of human catalase

1999 ◽  
Vol 55 (9) ◽  
pp. 1614-1615 ◽  
Author(s):  
R. A. P. Nagem ◽  
E. A. L. Martins ◽  
V. M. Gonçalves ◽  
R. Aparício ◽  
I. Polikarpov
Keyword(s):  
Search Model ◽  
Molecular Replacement ◽  
X Ray Diffraction ◽  
Beef Liver ◽  
X Ray ◽  
Diffusion Technique ◽  
Cell Dimensions ◽  
Synchrotron Radiation Diffraction ◽  
Replacement Solution ◽  
Unit Cell Dimensions

The enzyme catalase (H2O2–H2O2 oxidoreductase; E.C. 11.1.6) was purified from haemolysate of human placenta and crystallized using the vapour-diffusion technique. Synchrotron-radiation diffraction data have been collected to 1.76 Å resolution. The enzyme crystallized in the space group P212121, with unit-cell dimensions a = 83.6, b = 139.4, c = 227.5 Å. A molecular-replacement solution of the structure has been obtained using beef liver catalase (PDB code 4blc) as a search model.

The high-pressure cadmium borate Cd6B22O39·H2O

2015 ◽  
Vol 70 (3) ◽  
pp. 183-190 ◽  
Author(s):  
Gerhard Sohr ◽  
Nina Ciaghi ◽  
Klaus Wurst ◽  
Hubert Huppertz
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Structural Characteristics ◽  
X Ray Diffraction ◽  
X Ray ◽  
High Pressure High Temperature ◽  
Cell Dimensions ◽  
Temperature Experiment ◽  
Unit Cell Dimensions ◽  
Ir And Raman

AbstractSingle crystals of the hydrous cadmium borate Cd6B22O39·H2O were obtained through a high-pressure/high-temperature experiment at 4.7 GPa and 1000 °C using a Walker-type multianvil apparatus. CdO and partially hydrolyzed B2O3 were used as starting materials. A single crystal X-ray diffraction study has revealed that the structure of Cd6B22O39·H2O is similar to that of the type M6B22O39·H2O (M=Fe, Co). Layers of corner-sharing BO4 groups are interconnected by BO3 groups to form channels containing the metal cations, which are six- and eight-fold coordinated by oxygen atoms. The compound crystallizes in the space group Pnma (no. 62) [R1=0.0379, wR2=0.0552 (all data)] with the unit cell dimensions a=1837.79(5), b=777.92(2), c=819.08(3) pm, and V=1171.00(6) Å3. The IR and Raman spectra reflect the structural characteristics of Cd6B22O39·H2O.

X-Ray and Optical Data for a Rare Earth–Poor Eudialyte from the North–Central Alaska Range

1990 ◽  
Vol 5 (2) ◽  
pp. 89-92 ◽  
Author(s):  
Neil E. Johnson ◽  
Mickey E. Gunter ◽  
Diana N. Solie ◽  
Charles R. Knowles
Keyword(s):  
Rare Earth ◽  
Powder Diffraction ◽  
Weight Percent ◽  
Optical Data ◽  
Alaska Range ◽  
North Central ◽  
X Ray ◽  
The North ◽  
Cell Dimensions ◽  
Unit Cell Dimensions

AbstractPowder X-ray and optical data have been recorded for a sample of exceptionally rare earth-poor eudialyte (Na12(Ca, REE)6(Fe2+,Mn,Mg)3Zr3(Zr,Nb)x[Si9O27−y(OH)y]2[Si3O9]2(C1,F)z, with x = 0. 1–0.9, y = 1–3 and z = 0.7–1.4) from a pegmatitic vein associated with the peralkaline Windy Fork granite in the north–central Alaska range. The eudialyte is uniaxial positive with ω= 1.6062(2), ε= 1.6138 (3) and microprobe analyses indicate that the sum of REE + Yis less than 0.1 weight percent. Refined unit cell dimensions are: a = 14.2572(4), c = 30.1338(27), Dx= 2.67, F30= 128 (0.006, 42), M20= 76. An indexed powder diffraction pattern is given.

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