X-ray crystallography work

X-ray crystallography works by the scattering of X-rays from electrons and requires crystalline solids. If an organic compound is a liquid or is a solid but does not form good crystals, its structure cannot be determined in this way. 

For each crystal phase of TNT the observation of six i/ lines and six lines, indicating the presence of six Nitrogen NQR sites is in agreement with the x-ray crystallography work. There are two crystallographically distinct molecules per unit ceU, each with physically inequivalent nitro-groups. 

The three-dimensional structure of protein molecules can be experimentally determined by two different methods, x-ray crystallography and NMR. The interaction of x-rays with electrons in molecules arranged in a crystal is used to obtain an electron-density map of the molecule, which can be interpreted in terms of an atomic model. Recent technical advances, such as powerful computers including graphics work stations, electronic area detectors, and... 

As the classical Balz-Schiemann reaction is carried out in the solid state, the structures of the arenediazonium tetrafluoroborates as determined by X-ray crystallography must be the starting point for mechanistic investigations, as pointed out by Gougoutas (1979) in the context of his work on the X-ray structures of 3-carboxy-2-naphthalenediazonium bromide and iodide (see Secs. 4.2 and 10.6). 

A recent development in understanding the reactivity of bases has focused on their structures in solution and in the crystalline state. Due to the importance of dialkyl amide bases, there is a significant body of work, led by Williard and Collum , that has attempted to understand the structures of these reactive molecules. It is clear that they are aggregates. Lithium diisopropylamide (LiN/-Pr2) was isolated from a THF solution and X-ray crystallography revealed a dimeric structure (13 R = i-Pr, S = THF) in the... 

In late 1995, a team led by Vollhardt and Youngs reported their work on the strained PAM/PDM hybrid 80 [55]. Whereas the synthesis of 80 was not remarkable [Eq. (2)1, the solid-state behavior of the molecule was. X-ray crystallography revealed that the macrocycle was moderately strained, with the monoynes bent inward toward the center of the macrocycle by 3.9 -11.5° and the diyne unit bent outward by 8.6-11.2°. More importantly, crystal packing revealed that the diyne moieties were aligned in the prerequisite fashion for topochemical diacetylene polymerization to occur. Indeed, irradiation of crystals of 80 produced a violet... 

A determined by X-ray crystallography [56], whereas the distance to the amine groups deviates less, 2.09 A in this work and 2.01 A experimentally. Previous theoretical studies by Carloni et al. [63] and Zhang et al. [64] yielded Pt-Cl distances of 2.34 and 2.37 A, respectively. The difference from the more recently obtained value is related to the choice of basis set and exchange-correlation functional. 

CH3)C(-0C(CH3)2C(CH3)20-)+,41 Until the work described in this Review, the CI3+ and C(OH)3+ cations were the only trihalo- and trioxy-substituted cations to have been characterized by X-ray crystallography.23,42... 

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