Proton Transfer to a Hydridic Hydrogen in the Solid State

This is the first principle for determination of the potential energy surface. 

It is well known that a solvent can canse dramatic changes in rates and even mechanisms of chemical reactions. Modem theoretical chemistry makes it possible to incorporate solvent effects into calcnlations of the potential energy surface in the framework of the continnnm and explicit solvent models. In the former, a solvent is represented by a homogeneous medium with a bulk dielectric constant. The second model reflects specific molecule-solvent interactions. Finally, calculations of the potential energy surface in the presence or absence of solvents can be performed at various theory levels that have been considered in detail by Zieger and Autschbach [10]. 

PROTON TRANSFER TO A HYDRIDIC HYDROGEN IN THE SOLID STATE 

PROTON TRANSFER TO A HYDRIDE LIGAND IN SOLUTIONS OF TRANSITION METAL HYDRIDE COMPLEXES THEORY AND EXPERIMENT 

It should be emphasized that these two schemes are principally different. The second mechanism corresponds to a situation in which the formation of M- H bonds precedes the full proton transfer, while dihydrogen bonds can be formed only via direct protonation of the hydridic hydrogen. In addition, the protonation of the metal center can be slow at very fast transformation to the dihydrogen complex, masking detection of the dihydride molecule. Therefore, first, it is necessary to show what hydride center is protonated faster. 

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