Dihydrogen, ligand rotational model

One of the key indicators for the so-called nonclassical coordination in the solid state has been the observation of rotational transitions by INS [57,58]. These studies have led to a value for the rotational barrier of the dihydrogen ligand under the assumption of a model for this rotation. The barrier in turn was then tentatively analysed in terms of distinctive interactions by theoretical calculations or a series of experiments where one or more of these factors were changed. 

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