Fragmentation of molecular

There are several more or less strict approaches to describe the processes of formation and fragmentation of molecular ions. Unfortunately none of them is able to predict... 

The results of the next section strongly suggest that the C2H2 ion is formed by intact emission of acetylenic complexes and possible fragmentation of molecularly adsorbed ethylene. The other smaller ions are probably formed by simple fragmentation of acetylenic complexes and molecularly adsorbed ethylene, as well as by intact emission and simple fragmentation of other smaller hydrocarbon complexes. 

An alternative construction, termed fragment of molecular response [24], inserts the atomic partition of unity outside the derivative,... 

In these examples, the condensed Fukui functions were computed using Hirsh-feld population analysis [26], which is unique among the commonly employed population analysis methods, because the same results are obtained from the response of molecular fragment and the fragment of molecular response approaches [24]. There are other arguments in favor of the Hirshfeld scheme too [27,28], many of them based on the tendency for the atom-condensed Hirshfeld Fukui functions to be nonnegative [25,29,30]. Nonetheless, condensed Fukui functions maybe computed using any population analysis method common methods... 

Repeller An electrode used in thermospray ionization to effect fragmentation of molecular species. 

A. Internal State Distributions of the Fragments of Molecular Photodissociation... 

Heterocycles as intermediates in the synthesis and fragments of molecular knots 92NJC277. 

The protein globule of cytochrome P450 from the adrenal cortex consists of two fragments. The hydrophilic fragment FI has a molecular mass of 27000 and contains a heme and an adrenodoxin-binding site. The hydrophobic fragment of molecular mass 22000 binds the enzyme to the biomemrane. The presence of extensive hydrophobic portions has also been detected in liver cytochrome. 

Purposeful fragmentation of molecular ion peaks can be used to provide structural information. This technique has been exploited using ESI ionisation in conjunction with LC/MS for the identification of peptide and proteins. 

Boss A. P. (1995) Collapse and fragmentation of molecular cloud cores II. Collapse induced by stellar shock waves. Astrophys. J. 439, 224-236. 

As a soft ionization technique thermospray mass spectrometry often provides little fragmentation of molecular species. More importantly from the viewpoint of a metabolism chemist, thermospray accomplishes desorption ionization of extremely low vapor pressure analytes including intact glucuronide and sulfate conjugates. As demonstrated in the chapter by Brown and Draper in this proceedings, particle beam mass spectrometry does not have this capability. 

R. F. W. Bader, P. M. Beddall and J. Peslak Jr., A theoretical development of a virial relationship for spatially defined fragments of molecular systems, J. Chem. Phys. 58, 557-566 (1973). 

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