The title compound appears to be present in solution as one major (98%) and
two minor(ca, 1% each) isomers. All three isomers contain one bridging and
one terminal hydride ligand. However, they differ in the location of the t
erminal hydride. Proton T-1 measurements at variable temperature have allow
ed the determination of H-T-H-B distances in each isomer. An estimation of
the relative "hydridicity" of bridging and terminal hydrides has been gaine
d by measuring the T-1 of H-2(mu-H-2)Os-3(CO)(11), while insights into the
terminal/bridging hydride exchange have been gained from H-1 variable-tempe
rature: NMR.