Physical methods structure determination

X-rays Electromagnetic radiation with wavelengths ranging between 10"10 and lO cm. X-rays diffraction A physical method for determining the structure of crystalline solids by exposing the solids to X-rays and then studying the varying intensity of the difracted rays due to interference effects. 

Coordination chemistry relies heavily on a capacity to separate and/or isolate individual complexes from reaction mixtures, and subsequently to employ an array of physical methods to determine the nature and structure of such complexes. 

Microwave spectroscopy is the premier physical method for determining accurate and precise molecular structures, i.e. values of interatomic distances (bond distances) and angles (bond angles). This capability arises because the moments of inertia are directly related to the coordinates of the atoms as... 

Braude and Nachod, Determination of Organic Structures by Physical Methods, 1955 (Academic Press). 

A study of structural units, where a monomer is examined by physicochemical methods to determine its thermostability, its chemical and physical properties, and its sites of degradation. 

For more detailed discussion of dipole moments, see L. E. Sutton, in Determination of Organic Structures by Physical Methods, Vbl. 1, E. A. Braude and F. C. Nachod, eds., Academic Press, New York, 1955, Chapter 9 V I. Minkin, O. A. Osipov, and Y. A. Zhdanov, Dipole Moments in Organic Chemistry, Plenum Press, New York, 1970. 

Boden, N. In Determination of Organic Structures by Physical Methods Nachod, F.C. Zuck-erman, J.J., Ed. Academic Press New York, 1971 Vol. 4, Chapter 2. 

In general, physical methods have been used to study tautomerism more successfully than chemical methods, and, of the physical methods, those involving measurements of basicities and ultraviolet spectra are the most important, followed by those involving measurement of infrared and proton resonance spectra. An attempt is made here to delineate the scope and to indicate the advantages and disadvantages of the various methods. A short review by Mason of the application of spectroscopic methods appeared in 1955. Recently a set of reviews on the applications of physical methods to heterocyclic chemistry has appeared, which treats incidentally the determination of tautomeric structure. 

From Brundle, C.R. Robin, M.B., in Nachod Zuckerman Determination of Organic Structures by Physical Methods, Vol. 3 Academic Press NY, 1971, p. 18. 

Brown, H.C. McDaniel, D.H. Haflinger, O. in Braude Nachod Determination of Organic Structures by Physical Methods, vol. 1 Academic Rress NY, 1955, p. 567. 

Application of modem analytical procedures and physical methods for structure determination. In studies of microbial metabolism, the advantages resulting from the requirement for only extremely small quantities of material needed for gas- and liquid-chromatographic quantification, coupled to mass spectrometric identification, can hardly be overestimated. 

Spectrophotometric and spectrofluorimetric methods provide a wealth of information concerning structural determinations (identification, purity and precise measurement of concentration) and chemical changes in alkaloids. These techniques yield both quantitative and qualitative data on the effect of solvents, pH and other physiological conditions [141-143]. X-ray crystallography, H and NMR spectroscopy, infrared spectroscopy (IR) and circular dichroic spectroscopy were also used to study the physical properties... 

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