Molecular structure distortion

Molecular structure distorted octahedral (C4r) with the osmium atom slightly out of the X4 plane towards the nitride (in the case of [OsNC15]3 ). 

Figure 15.6 Various representations of the molecular structure of ryclc-Si2 showing S atoms in three parallel planes. I he idealized point group symmetry is and the mean dihedral angle is 86.1 5.5 . In the crystal the symmetry is slightly distorted to C21, and the central group of 6 S atoms deviate from eoplanarily by 14pm.

Especially notable is also the synthesis and structural characterization of an unusual antimony(III) guanidinate. 1,2,3-Tiiisopropylguanidine, Pr N = C(NHPr )2,was found to react with 1 molar equivalent of Sb(NMe2)3 in toluene under formation of a yellow solution, from which the novel compound Sb[Pr NC(NPr )2][Pr NHC(NPr )2] could be isolated in 10% yield as highly air-sensitive crystals. In the solid state, the complex adopts a heavily distorted trigonal-bipyramidal molecular structure in which the Sb is chelated by a [CfNPr ls] dianion and a [Pr NHC(NPr )2] monoanion (Figure 16). Supramolecular... 

Figure 11 (a) Molecular structure of (2), the distorted MeOH molecules are omitted " ... 

Currently, a wide variety of methods exists for calculating the molecular structure of large liquid crystal molecules which make use of pre-determined functional forms for the interactions in a molecule and semi-empirical information to parametrise the potentials. In general the interaction terms represent the energy cost of distorting bonds and bond angles from equilibrium. These can be expressed as... 

The molecular structure of the f-butyl derivative [BpBut]ZnBul has been determined by an x-ray diffraction study, which confirms a distorted trigonal planar coordination environment for zinc, as shown by the two views in Figs. 26 and 27 (80). In comparison to tetrahedral coordination, three-coordinate zinc alkyl complexes are rare (84). 

A series of copper(II) complexes with ring-substituted phen-ligands have been synthesized and their molecular structural and electronic structural properties have been investigated.246 Each structure ((280) r = 0.72, (281) r = 0.81, (282) r = 0.88, (283) r = 0.83, and (284) r = 0.68) is characterized by a distorted trigonal-bipyramidal arrangement of ligands around copper. 

Munakata et al. determined the molecular structures of the complexes (652) (quasi-tetrahedral) and (653) (distorted tetrahedron) and determined the nature of the bonding.518 Warren and... 

An important extension of lipid-solute interaction components [20] to membrane partitioning is provided by solute molecular structure. Spacing between polar and nonpolar regions (Fig. 8) within a solute molecule may result in significant distortion of the KpDm product across the membrane polar headgroup/lipid core interface [21], Such interactions may be responsible for deviations from projected transport predictions based on simple partitioning theory translating to deviations from predicted absorption kinetics [1],... 

Summary Organosilicon compounds, especially those containing numerous bulky (H3C)3Si substituents, show structural distortions, hindered dynamics, and unusual molecular properties such as record low first vertical ionization energies or extreme spin and charge delocalization. 

Figure 4. Views of DMBA, BP, 5,6-dimethylchrysene, 5,12-dimethyl-chrysene and 5-methyl chrysene. These illustrate the distortions that occur as a result of steric effects. These and many subsequent representations of molecular structure are stereoviews and may be viewed with stereoglasses alternatively the reader can focus his eyes on the two images until an image between them begins to form and then allow his eyes to relax until the central image becomes three-dimensional. This process calls for patience and may take a minute or so. The reader who does not wish to do this may simply inspect one of the two diagrams for each structure.

The molecular structure of the closo 12-vertex 1-SBnHn cluster (17) has been studied by electron diffraction methods augmented by ab initio calculations. Substantial distortions away from the regular icosahedron occurred by expansion of the pentagonal belt adjacent to sulfur.73 The UV-PES spectra of 17 has also been reported,71 and its microwave spectrum has been investigated and demonstrated that the molecule had C5v symmetry.74... 

The complex trans-[Cun(hfac)2(TTF—CH=CH—py)2](BF4)2-2CH2Cl2 was obtained after 1 week of galvanostatic oxidation of Cun(hfac)2(TTF CH=CH py)2 [61]. The molecular structure of the copper complex is identical to its neutral form. There is one TTF CH=CH py molecule per BF4 and one dichloromethane solvent molecule. The copper is located at the center of a centrosymetric-distorted octahedron two TTF CH=CH py ligands in trans- conformation are bonded to Cun by the nitrogen atoms of the pyridyl rings. From the stoichiometry, the charge distribution corresponds to fully oxidized TTF CH=CH—py+" radical units. 

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