Synthesis and Spectroscopic and Theoretical Characterization of the Elongated Dihydrogen Complex OsCl 2 (η 2 -H 2 )(NHCPh 2 )(P i Pr 3 ) 2

The referred elongated dihydrogen compounds cannot be described by simply interpolating dihydrogen and dihydrido models. According to the results reported here, it is more appropriate to describe them as complexes containing two hydrogen atoms moving freely in a wide region of the coordination sphere of the metal.