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).

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.

scholarly journals The reaction of 3,5-diphenyl-1,2-dithiolium-4-olate with aniline: the crystal structure of 1-phenylimino-2-phenylamino-3-phenylindene

1987 ◽  
Vol 65 (12) ◽  
pp. 2830-2833 ◽  
Author(s):  
David M. McKinnon ◽  
Peter D. Clark ◽  
Robert O. Martin ◽  
Louis T. J. Delbaere ◽  
J. Wilson Quail
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Single Crystal ◽  
Least Squares ◽  
Direct Methods ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cell Dimensions ◽  
Unit Cell Dimensions

3,5-Diphenyl-1,2-dithiolium-4-olate (1) reacts with aniline to form 1-phenylimino-2-phenylamino-3-phenylindene (3a). Under suitable conditions, 6-phenylbenzo[b]indeno[1,2-e]-1,2-thiazine is also formed. These structures are confirmed by alternative syntheses. The molecular structure of 3a has been determined by single crystal X-ray diffraction. Compound 3a crystallizes in the monoclinic space group C2/c with unit cell dimensions a = 20.777(3) Å, b = 6.130(3) Å, c = 31.327(3) Å, 3 = 99.59(1)°, and Z = 8. The structure was solved by direct methods and refined by least squares to a final R = 0.055. The molecular structure of 3a shows the three phenyl containing substituents to have the planes of their ring systems tilted between 40° and 60° from the plane of the indene system due to steric repulsions.

Crystal and Molecular Structure of Cycasin, (Z)-β-D-Glucopyranosyloxy-NNO-azoxymethane

1995 ◽  
Vol 48 (5) ◽  
pp. 1059 ◽  
Author(s):  
ME Tate ◽  
IM Delaere ◽  
GP Jones ◽  
ERT Tiekink
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Structure Analysis ◽  
Crystal And Molecular Structure ◽  
Crystal Structure Analysis ◽  
Monoclinic Space Group ◽  
Cell Dimensions ◽  
Cycas Revoluta ◽  
Unit Cell Dimensions

Characterization of cycasin , (Z)-β-D-glucopyranosyloxy-NNO-azoxymethane, from Cycas revoluta Thunb . is reported. A crystal structure analysis shows the azoxy substituents adopt a Z configuration. The colourless crystals are monoclinic, space group C2 with unit cell dimensions a 15.409(4), b 4.855(4), c 15.752(4) Ǻ, β 109.87(2)°, Z 4; the structure was refined to final R 0.033, 886 reflections with I ≥ 3.0σ(I) being used.

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.

Perchlorato, Nitrato, and Acetylacetonato Complexes of Copper(I). The Crystal and Molecular Structure of Perchloratobis(tricyclohexyiphosphine)Copper(I)

1975 ◽  
Vol 53 (13) ◽  
pp. 1949-1957 ◽  
Author(s):  
Roderic J. Restivo ◽  
Abraham Costin ◽  
George Ferguson ◽  
Arthur J. Carty
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Infrared Spectra ◽  
Copper Atom ◽  
Crystal And Molecular Structure ◽  
Three Dimensional ◽  
Monoclinic Space Group ◽  
X Ray ◽  
Tertiary Phosphines ◽  
Cell Dimensions

Copper(I) perchlorate, nitrate, and acetylacetonate complexes of the types Cu(triphos)ClO4 (triphos = CH3C(CH2PPh2)3), Cu(Cy3P)2ClO4 (Cy3P = P(C6H11)3), Cu(triphos)NO3, Cu(Cy3P)2(HFac)(HFac = hexafluoroacetylacetonate), and Cu (Cy3P)2(TtFac) (TtFac = thienyltrifluoroacetylacetonate) have been synthesized by reduction of the corresponding perchlorate, nitrate, and acetylacetonates with tertiary phosphines. Infrared spectra indicate the presence of monodentate perchlorate groups in Cu(triphos)ClO4 and in Cu(Cy3P)2ClO4 and the crystal structure of the latter has been determined by a three-dimensional X-ray analysis using diffractometer data. The crystals are monoclinic, space group C2/c, with cell dimensions a = 18.159(6), b = 9.493(2), c = 22.182(3) Å, and β = 95.41(2)° and four molecules per unit cell. The structure was refined by block-diagonal least squares methods to a final R of 0.051 for 2617 reflections using anisotropic thermal parameters for the nonhydrogen atoms. The structure consists of discrete Cu(Cy3P)2ClO4 molecules with symmetry C2 separated by normal van der Waals distances. The copper atom is three-coordinate and the perchlorate anion is monodentate but disordered over two sites. Principal dimensions include: Cu—P 2.262(1) Å, Cu—O 2.220(7) Å, [Formula: see text][Formula: see text] and 99.8(2)°, and [Formula: see text]

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

The cycloaddition of norbornadiene to (triphenylphosphoranediyl)aminocyclotrithiatriazene; the crystal and molecular structure of Ph3PN—S3N3•C7H8

1983 ◽  
Vol 61 (9) ◽  
pp. 2062-2067 ◽  
Author(s):  
Stephen W. Liblong ◽  
Richard T. Oakley ◽  
A. Wallace Cordes ◽  
Mark C. Noble
Keyword(s):  
Molecular Structure ◽  
Crystal And Molecular Structure ◽  
Direct Methods ◽  
Chair Conformation ◽  
Monoclinic Space Group ◽  
Frontier Orbitals ◽  
Full Matrix ◽  
X Ray ◽  
X Ray Crystallography ◽  
Kinetics Of

The reaction of norbornadiene with (triphenylphosphoranediyl)aminocyclotrithiatriazene produces the cycloadduct Ph3PN—S3N3•C7H8. The crystal and molecular structure of this compound has been determined by X-ray crystallography. Crystals of Ph3PN—S3N3•C7H8 are monoclinic, space group P21/c, a = 9.757(1), b = 15.114(1), c = 16.535(2) Å, β = 100.73(1)°, V = 2395.7(9) Å3, and Z = 4. The structure was solved by direct methods and refined by Fourier and full-matrix least-squares procedures to give a final R of 0.040 and Rw of 0.058 for 2620 observed reflections. The structure reveals that the S3N3 ring adds to norbornadiene in an exo fashion via two sulphur atoms. The S3N3 ring adopts a chair conformation with the three ligands occupying axial positions on the same side of the ring. The relative rates of this and other cycloadditions involving SN substrates and olefins are discussed in terms of the energies of the interacting frontier orbitals. The results suggest that HOMO(olefin)–LUMO(SN substrate) interactions control the kinetics of these reactions.

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.

Cyclische Diazastannylene, III1 Die Kristall-und Molekülstruktur der monoklinen Phase von 1.3-Di-tert-butyl-2.2-dimethyl-1.3.2.4λ2 -diazasilastannetidin / The Crystal and Molecular Structure of the Monoclinic Phase of 1,3-Di-feri-butyl-2,2-dimethyl-1,3,2,4λ2 -diazasilastannetidine

1978 ◽  
Vol 33 (1) ◽  
pp. 7-13 ◽  
Author(s):  
M. Veith
Keyword(s):  
Molecular Structure ◽  
Monoclinic Phase ◽  
Crystal And Molecular Structure ◽  
Three Dimensional ◽  
Monoclinic Space Group ◽  
Site Symmetry ◽  
Space Group ◽  
X Ray ◽  
Tert Butyl ◽  
Cell Dimensions

Abstract The crystal and molecular structure of the monoclinic phase of 1,3-di-tert-butyl-2,2-dimethyl-1,3,2,4λ2 -diazasilastannetidine has been determined from three-dimensional X-ray data collected on a two-circle diffractometer at -120 °C (MoKa radiation, 2623 reflexions, R - 0,050). The crystals are monoclinic, space group C2/c, with cell dimensions a = 10.655(5), b = 25.75(1), c = 17.33(1) Å, β = 106.8(1)° and Z = 12. Four monomeric (crystal site symmetry 2 (C2)) and four dimeric units (crystal site symmetry 1̄ (Ci)) are present in the structure interacting over tin-tin (3.68 Å). Remarkable are the very short Sn-N bond (2.09 Å) in the monomer and the donation bond Sn-N (2.39 Å) in the dimer. The coordination of the tin atoms in the different units is discussed in detail.

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.

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