ChemInform Abstract: STEREOSPECIFIC TEMPLATE SYNTHESIS OF A MACROTETRACYCLIC HEXAAZACRYPTATE: X-RAY CRYSTAL STRUCTURE O

1985 ◽  
Vol 16 (39) ◽  
Author(s):  
R. J. GEUE ◽  
M. G. MCCARTHY ◽  
A. M. SARGESON ◽  
B. W. SKELTON ◽  
A. H. WHITE
Keyword(s):  
Crystal Structure ◽  
Template Synthesis ◽  
X Ray

Platinum(II) Template Synthesis of a Pendant-Arm Macrocycle

1998 ◽  
Vol 51 (9) ◽  
pp. 871 ◽  
Author(s):  
Hong Xiao ◽  
Geoffrey A. Lawrance ◽  
Trevor W. Hambley
Keyword(s):  
Crystal Structure ◽  
Template Synthesis ◽  
Crystal Structure Analysis ◽  
Macrocyclic Complex ◽  
Triclinic Space Group ◽  
X Ray ◽  
Pendant Arm ◽  
Major Isomer ◽  
Square Planar ◽  
R Value

Platinum(II)-directed condensation of ethane-1,2-diamine with nitroethane and formaldehyde yields the colourless macrocyclic complex (trans-6,13-dimethyl-6,13-dinitro-1,4,8,11-tetraazacyclotetradecane)plat- inum(II), [Pt(1)]2+, in good yield. This parallels chemistry reported earlier around other triad members nickel(II) and palladium(II). The pendant nitro groups in the major isomer are disposed on opposite sides of the macrocycle in a trans geometry, as confirmed by the X-ray crystal structure analysis of [Pt(1)] (ClO4)2, which crystallizes in the triclinic space group P-1, a 8·041(4), b 8·482(4), c 9·443(3) Å, α 69·44(3), β 67·66(4), γ 71·73(4)°,Z1, and was refined to an R value of 0·027 on 1920 F. The platinum ion lies in a square planar environment of four nitrogen donors, with typical Pt–N distances; comparisons between the platinum(II) and palladium(II) complexes of (1) and its analogue (2), with diammonio groups in place of dinitro groups, are discussed

The template synthesis and X-ray crystal structure of the first dinuclear lanthanide(III) iminophenolate cryptate

1999 ◽  
pp. 125-126 ◽  
Author(s):  
Fernando Avecilla ◽  
Andrés de Blas ◽  
Carlos Platas ◽  
Teresa Rodríguez-Blas ◽  
Rufina Bastida ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Template Synthesis ◽  
X Ray

A study on α-RuCl3 crystal structure by scanning tunneling microscopy

1989 ◽  
Vol 47 ◽  
pp. 30-31
Author(s):  
H.-J. Cantow ◽  
H. Hillebrecht ◽  
S. Magonov ◽  
H. W. Rotter ◽  
G. Thiele
Keyword(s):  
Crystal Structure ◽  
Density Distribution ◽  
Scanning Tunneling Microscopy ◽  
Electron Density ◽  
Structure Determination ◽  
Electron Density Distribution ◽  
Scanning Tunneling ◽  
Monoclinic Space Group ◽  
Tunneling Microscopy ◽  
X Ray

From X-ray analysis, the conclusions are drawn from averaged molecular informations. Thus, limitations are caused when analyzing systems whose symmetry is reduced due to interatomic interactions. In contrast, scanning tunneling microscopy (STM) directly images atomic scale surface electron density distribution, with a resolution up to fractions of Angstrom units. The crucial point is the correlation between the electron density distribution and the localization of individual atoms, which is reasonable in many cases. Thus, the use of STM images for crystal structure determination may be permitted. We tried to apply RuCl3 - a layered material with semiconductive properties - for such STM studies. From the X-ray analysis it has been assumed that α-form of this compound crystallizes in the monoclinic space group C2/m (AICI3 type). The chlorine atoms form an almost undistorted cubic closed package while Ru occupies 2/3 of the octahedral holes in every second layer building up a plane hexagon net (graphite net). Idealizing the arrangement of the chlorines a hexagonal symmetry would be expected. X-ray structure determination of isotypic compounds e.g. IrBr3 leads only to averaged positions of the metal atoms as there exist extended stacking faults of the metal layers.

X-ray Crystal Structure of ?9-THC-tosylate

Planta Medica ◽  
2008 ◽  
Vol 74 (03) ◽  
Author(s):  
W Gul ◽  
P Carvalho ◽  
D Slade ◽  
M Avery ◽  
JR Duchek ◽  
...  
Keyword(s):  
Crystal Structure ◽  
X Ray

Crystal structure of an inclusion complex between chiral monoaza-15-crown-5 and S(–)-1-phenyl-ethyl ammonium percholorate

2003 ◽  
Vol 218 (5) ◽  
Author(s):  
Süheyla Özbey ◽  
F. B. Kaynak ◽  
M. Toğrul ◽  
N. Demirel ◽  
H. Hoşgören
Keyword(s):  
Crystal Structure ◽  
Inclusion Complex ◽  
Single Crystal ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
New Type

AbstractA new type of inclusion complex, S(–)-1 phenyl ethyl ammonium percholorate complex of R-(–)-2-ethyl - N - benzyl - 4, 7, 10, 13 - tetraoxa -1- azacyclopentadecane, has been prepared and studied by NMR, IR and single crystal X-ray diffraction techniques. The compound crystallizes in space group

Single Crystal Growth of High-Pressure Phases of Ice and Salt Hydrate Far Below the Original Melting Point by Mixing Alcohol: Crystal Structure Determination of Magnesium Chloride Heptahydrate

2020 ◽  
Author(s):  
Keishiro Yamashita ◽  
Kazuki Komatsu ◽  
Hiroyuki Kagi
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Crystal Growth ◽  
Single Crystal ◽  
Room Temperature ◽  
Growth Technique ◽  
Salt Hydrate ◽  
X Ray

An crystal-growth technique for single crystal x-ray structure analysis of high-pressure forms of hydrogen-bonded crystals is proposed. We used alcohol mixture (methanol: ethanol = 4:1 in volumetric ratio), which is a widely used pressure transmitting medium, inhibiting the nucleation and growth of unwanted crystals. In this paper, two kinds of single crystals which have not been obtained using a conventional experimental technique were obtained using this technique: ice VI at 1.99 GPa and MgCl<sub>2</sub>·7H<sub>2</sub>O at 2.50 GPa at room temperature. Here we first report the crystal structure of MgCl2·7H2O. This technique simultaneously meets the requirement of hydrostaticity for high-pressure experiments and has feasibility for further in-situ measurements.

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