The M–H bond stretching frequencies of µ₂-bridged metal hydrides and their relationship to the M–H–M interbond angle

Solution Equilibria in YbDOTMA, a Chiral Analogue of One of the Most Successful Contrast Agents for MRI, GdDOTA

“…It should be observed that the solution of this optimization is unique, which excludes a rotation of the methyl acetate as the origin of the two forms, in agreement also with other findings on similar structures. [13] An equivalent set was provided by the following stereochemical operations on these structures: (i) mirror image (inversion) of the whole complex; (ii) epimerization of the four only the large difference between the anisotropy factors, D D and D d , justifies the appearance of two distinct sets of sig-C α stereocentres (these operations must be followed again by the carboxylate rotation). The result was once more a nals for the two isomers.…”

“…[13] [33] The detailed comparison with the kinetic rates of DOTA is not straightforward, owing to the different moThe populations of all the four DOTMA structures must be expected to be different. Indeed, only two species could lar ratios of the forms in the two complexes.…”

Ab initiocluster calculations of hydrogenated GaAs(001) surfaces

“…These results agree with previous studies of bridging hydrogen bonds in metal hydride clusters. 40 The large Ga 1 -H 4 -Ga 2 bond angles observed for hydrogen insertion into the gallium dimers on GaAs͑001͒ are due to the Ga-As back bonds, which try to pull the Ga atoms back to their bulk lattice positions (aϭ4 Å͒.…”

Guided ion beam studies of the reactions of Fe+n (n=2–15) with D2: Cluster–deuteride bond energies as a chemical probe of cluster structures

“…The asymmetric cluster-deuteride stretching frequency can be estimated from the symmetric stretch by multiplying by tan͑/2͒, where is the included angle of the M-H-M bridged species. 30 Values of varying from 80°to 90°can be estimated from reported M-H and M-M bond distances calculated for hydrogen on iron surfaces 31 and on an Fe 12 cluster 29 as well as from crystal structure measurements of organometallic species. 32 The average value yields an estimate for the asymmetric cluster-deuteride stretching frequency of 870 cm Ϫ1 .…”