The dissocn. of peptide ions has been found to have ultrafast components that in many ways are uniquely different from typical unimol. kinetics. As such, some peptide reactions provide new channels, which do not conform to statistical models of reaction kinetics. When the dissocn. rates are in the 100 fs range, they are in a time scale where statistical methods do not yet apply, although mols. that have not yet dissocd. will later in time undergo statistical redistribution of their excess energy, which, however, may not lead to noticeable reactivity within the exptl. time frames for large peptides and hence are simply dissipative. This work is meant to reconcile the long time statistical results of Lifshitz et al. (2003) with the work of Schlag et al. (1995/6) that suggests an alternate parallel and much faster time scale for dissocn. It is argued that the two sets of results and interpretations augment one another and in fact open up a most interesting new field of peptide kinetics in addn. to the unimol. behavior, which becomes de facto arrested by the shear size of the mol. being unable to find a transition state on any reasonable time scale. [on SciFinder(R)]     «

The dissocn. of peptide ions has been found to have ultrafast components that in many ways are uniquely different from typical unimol. kinetics. As such, some peptide reactions provide new channels, which do not conform to statistical models of reaction kinetics. When the dissocn. rates are in the 100 fs range, they are in a time scale where statistical methods do not yet apply, although mols. that have not yet dissocd. will later in time undergo statistical redistribution of their excess energy...     »

Molecular structure-property relationship (charge-transfer kinetics of photoionized peptides dissocn. studying charge transfer from arom. chromophores in peptide chain by MS) Statistical mechanics (degrees of freedom kinetics of photoionized peptides dissocn. studying charge transfer from arom. chromophores in peptide chain by MS) Statistical analysis (kinetics of photoionized peptides dissocn. by statistical anal.) Chromophores Dissociation Dissociation kinetics Electron transfer Energy level excitation Molecular dynamics Molecular rotation Photoionization Potential energy UV radiation (kinetics of photoionized peptides dissocn. studying charge transfer from arom. chromophores in peptide chain by MS) Peptides Role: CPS (Chemical process), PEP (Physical, engineering or chemical process), PRP (Properties), PYP (Physical process), PROC (Process) (kinetics of photoionized peptides dissocn. studying charge transfer from arom. chromophores in peptide chai peptide ion dissocn kinetics statistical model charge transfer MS     «

Molecular structure-property relationship (charge-transfer kinetics of photoionized peptides dissocn. studying charge transfer from arom. chromophores in peptide chain by MS) Statistical mechanics (degrees of freedom kinetics of photoionized peptides dissocn. studying charge transfer from arom. chromophores in peptide chain by MS) Statistical analysis (kinetics of photoionized peptides dissocn. by statistical anal.) Chromophores Dissociation Dissociation kinetics Electron transfer Energy level e...     »