Experimental and Theoretical Studies on 1,4,5,7-Dithiadiazepinyl Radicals:  Preparation and X-ray Structure of 5-(Trimethylsilyl)tetrachlorobenzo-1,4,5,7-dithiadiazepine

1997 ◽  
Vol 36 (21) ◽  
pp. 4772-4777 ◽  
Author(s):  
Vadapalli Chandrasekhar ◽  
Tristram Chivers ◽  
Masood Parvez ◽  
Ignacio Vargas-Baca ◽  
Tom Ziegler
Keyword(s):  
Theoretical Studies ◽  
X Ray ◽  
Experimental And Theoretical Studies

Experimental and theoretical studies of the mica polymorphs

1956 ◽  
Vol 31 (234) ◽  
pp. 209-235 ◽  
Author(s):  
J. V. Smith ◽  
H. S. Yoder
Keyword(s):  
Growth Mechanism ◽  
Theoretical Study ◽  
Dominant Role ◽  
Spiral Growth ◽  
Theoretical Studies ◽  
X Ray ◽  
Layer Cell ◽  
Triclinic Structure ◽  
Experimental And Theoretical Studies ◽  
Made In

SummaryAn experimental and theoretical study has been made in order to determine the number and the structure of the possible polymorphs and to determine the structural relations between them. The simplest structures are 1M, 2M1, 2M2, 3T, 20, and 6H polymorphs, and more complicated types can be developed. Some of the previously described polymorphs were not contained in the theoretical list and were re-examined. The 6M structure was found to be a 2M2 polymorph, the 6-layer triclinic type was found to be a 2M1 polymorph, and the 3M structure was shown to be a 3T type. The 24-layer triclinic structure could be described on a simpler 8-layer cell. This type together with a new 12-layer monoclinic structure, as well as other structures of higher periodicity, presumably consists of complex stacking and results from spiral-growth mechanism. Two extreme types of layer-disordered crystals may be built and a disorder of individual ions may also occur. Single stacking faults result in twinned crystals. A new twin relation (180° rotation about the [100] axis) has been recognized. Twenty specimens from extreme geological environments have been examined in order to evaluate the control of environment on the stacking. The type of stacking could not be attributed solely to the influence of pressure and temperature. Composition appears to play a dominant role in the type of stacking, and semi-quantitative structural arguments appear to support this contention. The influence of growth mechanism is discussed. A scheme for the identification of the mica polymorphs by X-ray powder and single-crystal methods is given.

Experimental and theoretical studies of the physical processes occurring in thin plane targets irradiated by intense X-ray pulses

2007 ◽  
Vol 33 (6) ◽  
pp. 444-454 ◽  
Author(s):  
A. É. Bugrov ◽  
I. N. Burdonskiĭ ◽  
V. V. Gavrilov ◽  
A. Yu. Gol’tsov ◽  
E. V. Grabovskiĭ ◽  
...  
Keyword(s):  
Theoretical Studies ◽  
Physical Processes ◽  
X Ray ◽  
Experimental And Theoretical Studies

X-ray near-edge structure of the II-VI compounds containing manganese: Experimental and theoretical studies ofCd1−xMnxTe andZn1−xMnxTe

1991 ◽  
Vol 44 (20) ◽  
pp. 11075-11084 ◽  
Author(s):  
A. Kisiel ◽  
A-I. Ali Dahr ◽  
P. M. Lee ◽  
G. Dalba ◽  
P. Fornasini ◽  
...  
Keyword(s):  
Theoretical Studies ◽  
Edge Structure ◽  
X Ray ◽  
Experimental And Theoretical Studies

scholarly journals Texture Development and Anisotropic Photoelastic Properties in Rolled Silver Chloride

1995 ◽  
Vol 24 (1-3) ◽  
pp. 105-119
Author(s):  
P. Dietz ◽  
H. Gieleßen
Keyword(s):  
Elastic Anisotropy ◽  
Silver Chloride ◽  
Monochromatic Light ◽  
Theoretical Studies ◽  
X Ray ◽  
State Of Stress ◽  
Cold Rolled ◽  
Polycrystalline Silver ◽  
Experimental And Theoretical Studies ◽  
Relative Retardation

Experimental and theoretical studies have been carried out in order to relate elastic anisotropy to optical anisotropy by means of photoelasticity. The fundamentals of anisotropic photoelasticity have been described. Specimens of monocrystalline and polycrystalline silver chloride have been submitted to tensile stress and relative retardation and extinction angles observed in polarized monochromatic light to show conformity to the theories which quantitatively relate the state of stress and optical phenomena. Textures of cold-rolled as well as of recrystallized silver chloride specimens were determined with an X-ray goniometer. Texture determining parameters such as degree of rolling and recrystallisation time and temperature have been varied. Textures found in silver chloride after various processing have been characterized.

scholarly journals A SF5 Derivative of Triphenylphosphine as an Electron-Poor Ligand Precursor for Rh and Ir Complexes

Molecules ◽  
2020 ◽  
Vol 25 (17) ◽  
pp. 3977
Author(s):  
Maria Talavera ◽  
Silke Hinze ◽  
Thomas Braun ◽  
Reik Laubenstein ◽  
Roy Herrmann
Keyword(s):  
Dft Calculations ◽  
Cone Angle ◽  
Molecular Structures ◽  
Theoretical Studies ◽  
Rhodium Complexes ◽  
Coupling Constant ◽  
X Ray Diffraction ◽  
X Ray ◽  
Experimental And Theoretical Studies

The synthesis of the triarylphosphine, P(p-C6H4SF5)3 containing a SF5 group, has been achieved. The experimental and theoretical studies showed that P(p-C6H4SF5)3 is a weaker σ-donor when compared with other substituted triarylphosphines, which is consistent with the electron-withdrawing effect of the SF5 moiety. The studies also revealed a moderate air stability of the phosphine. The σ-donor capabilities of P(p-C6H4SF5)3 were estimated from the phosphorus-selenium coupling constant in SeP(p-C6H4SF5)3 and by DFT calculations. The behavior of P(p-C6H4SF5)3 as ligand has been investigated by the synthesis of the iridium and rhodium complexes [MCl(COD){P(p-C6H4SF5)3}], [MCl(CO)2{P(p-C6H4SF5)3}2] (M = Ir, Rh), or [Rh(µ-Cl)(COE){P(p-C6H4SF5)3}]2, and the molecular structures of [IrCl(COD){P(p-C6H4SF5)3}] and [Rh(µ-Cl)(COE){P(p-C6H4SF5)3}]2 were determined by single X-ray diffraction. The structures revealed a slightly larger cone angle for P(p-C6H4SF5)3 when compared to other para-substituted triarylphosphines.

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