Elongated dihydrogen versus compressed dihydride complexes: the temperature dependence of the H-D spin-spin coupling constant as a criterion to distinguish between them
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Updated: Aug 13, 2026

Analyzing Protein Dynamics Using Hydrogen Exchange Mass Spectrometry
Published on: November 29, 2013
Ricard Gelabert1, Miquel Moreno, José M Lluch
1Universitat Autònoma de Barcelona, Departament de Química, Bellaterra, Barcelona, Spain.
Abstract:
To be able to propose experimental tests to distinguish elongated dihydrogen transition-metal complexes from compressed dihydride transition-metal complexes, a thorough density functional study of the electronic structure in combination with quantum nuclear dynamics calculations have been performed for complexes [Cp*Ru(H2PCH2PCH2(H2)]+ and [CpRe(CO)2H2]. The results of this study suggest that elongated dihydrogen complexes and compressed dihydride complexes have different properties and that it should be possible to distinguish between them experimentally. In particular, different behavior is predicted with respect to 1) the sign of the isotope geometric effect on the H-H distance at 0 K, 2) the temperature dependence of the H-H distance, and 3) the temperature dependence of the H-D spin-spin coupling constant in 1H NMR spectroscopy.
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