Determination of dissociation energies by use of energy-dependent decay pathway branching ratios

We present a method for the determination of dissociation energies of polya tomic systems that undergo sequential fragmentation with energy-dependent d ecay pathway branching. It allows to experimentally determine the dissociat ion energy of any polyatomic system that shows such fragmentation behaviour without the need for a specific modelling of the system or of its fragment ation process, thus eliminating several systematic errors of traditional me thods. The new method has been applied to the sequential fragmentation of A u-14(+) and Au-16(+). The resulting dissociation energies are highly accura te and in good agreement with model-free values based on rates of sequentia l decays. (C) 2001 Elsevier Science B.V. All rights reserved.