Complex molecular structure analysis

Most researchers find it useful to employ three-dimensional graphics representations of peptides and proposed mimetics in their studies. This rudimentary level of molecular modeling allows for manipulation and geometric comparison of complex molecular structures. Using standard molecular bonding parameters, this level of analysis can test whether the proposed mimetic has the possibility of adopting the desired conformation, so that it can present important molecular recognition features in the appropriate orientation. 

Near-infrared spectroscopy (NIRS) can be used for product identification, classification and quality control, as well as for the determination of product properties (chemical and physical) and component concentrations in process applications, all with the object of rapid analysis. Near-IR analysis was born of a need to solve practical quality control problems rather than the desire to perform high-resolution molecular structure analysis in the laboratory. The samples subjected to NIRS are often very complex mixtures and are studied without any sample preparation. Competitor analysis is not possible. 

Methods for the Analysis of Complex Molecular Structures with the Aid of X-Rays, Colloid Chemistry Theoretical and Applied, Vol. V, edited hy J. Alexander (l9i i ). 

IX. The analysis of complex molecular structure The structure of cyclo-artenol ... 

LEED is the most powerfiil, most widely used, and most developed technique for the investigation of periodic surface structures. It is a standard tool in the surface analysis of single-crystal surfaces. It is used very commonly as a method to check surface order. The evolution of the technique is toward greater use to investigate surface disorder. Progress in atomic-structure determination is focused on improving calculations for complex molecular surface structures. 

The crystal structure analysis of the parent 1,2,3-triazole in the solid state unambiguously demonstrated that it crystallizes as a 1 1 molecular complex of both possible tautomers 24a and 24b, linked by a N-H - N hydrogen bond [97AX(C)1846]. 

The analysis of phosphates and phosphonates is a considerably complex task due to the great variety of possible molecular structures. Phosphorus-containing anionics are nearly always available as mixtures dependent on the kind of synthesis carried out. For analytical separation the total amount of phosphorus in the molecule has to be ascertained. Thus, the organic and inorganic phosphorus is transformed to orthophosphoric acid by oxidation. The fusion of the substance is performed by the addition of 2 ml of concentrated sulfuric acid to — 100 mg of the substance. The black residue is then oxidized by a mixture of nitric acid and perchloric acid. The resulting orthophosphate can be determined at 8000 K by atom emission spectroscopy. The thermally excited phosphorus atoms emit a characteristic line at a wavelength of 178.23 nm. The extensity of the radiation is used for quantitative determination of the phosphorus content. 

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