Neutral metal-ligand bonds, bond energy determination

The application of newer methods to studies of gas phase organometallic reactions will lead to the development of routine techniques for determination of the thermochemistry of organometallic species. The examples discussed above demonstrate that an analysis of kinetic energy release distributions for exothermic reactions yields accurate metal ligand bond dissociation energies. This can be extended to include neutrals as well as ions. For example, reaction 15 has been used to determine accurate bond dissociation energies for Co-H and C0-CH3 (57). 

AH (M0H ) was determined. In some instances AH of the ion is known and the corresponding neutral is not. Thus, proton bracketing experiments can also be used to determine neutral metal-ligand bond energies. Reaction 8, for example, was used to determine PA(4-vinyl-... 

In this review we discuss five techniques involving Fourier transform mass spectrometry (FTMS) for determining qualitative and quantitative metal ion-ligand bond energies. These include (i) exothermic ion-molecule reactions, (ii) equilibrium measurements, (iii) competitive collision-induced dissociation, (iv) endothermic ion-molecule reactions, and (v) photodissociation. A key advantage of the FTMS methodology is its ion and neutral manipulation capabilities which permit the formation and study of a limitless number of interesting metal-ion systems. 

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