Proton spin-lattice NMR relaxation studies of hydride carbonyl clusters: a method to evaluate distances involving hydrido ligands

Deuterium Quadrupolar Coupling Constants of Deuteride Bridging Ligands: A Study on Rhenium Hydrido Carbonyl Clusters

“…1 H relaxation basically depends on dipole−dipole interaction and provides spatial relationship. In organometallic chemistry short relaxation times of hydrogens bound to a metal can be a signature of the occurrence of a nonclassical dihydrogen ligand in the absence of a significant dipolar contribution of the metal itself. , Differential dipolar contributions to the hydrido ligand relaxation provided structural assignments, distances in good agreement with the neutron diffraction data, and proved the occurrence of hydrogen or dihydrogen bond interactions in solution …”

Coordination of Imines on Os3Clusters: Effect of the Solvent in Addressing Isomer Formation

“…Further an accurate determination may be obtained by the isolation of the selective H,H dipolar term. In our system this goal is easily achieved by the comparison of the T 1 values of the two isotopomers, H(μ-H)Os 3 (CO) 10 (HNC(CH 3 ) 2 ) and H(μ-H)Os 3 (CO) 10 (DNC(CH 3 ) 2 ). − …”

Coordination of an Imine Ligand on an Os3Cluster Stabilized by Intramolecular Os−H---H−N Hydrogen Bonding

“…On these grounds, it was possible to evaluate the dipolar contribution of the imine proton to the relaxation of the terminal and bridging hydrides. From these values actual H−H distances can be estimated according to , where the molecular reorientational time τ c is equal to 0.618/ω 0 (ω 0 = 2π400 × 10 6 rad s -1 ), i.e., 2.45 × 10 -10 rad s -1 . The resulting r H,H distances were 2.1 ± 0.1 Å and 2.7 ± 0.1 Å for the terminal and the bridging hydride, respectively.…”