Differential anomalous x-ray scattering evidence for the existence of .mu.-H3O2- bridging ligands in solution

Differential anomalous X-ray scattering has been used to confirm the existence of ..mu..-H/sub 3/O/sub 2//sup -/ bridging ligands in aqueous solutions. Dimers and higher polymers of the trinuclear cluster (M/sub 3/O/sub 2/(O/sub 2/CR)(H/sub 2/O)/sub 3/)/sup 2 +/ (M = W, Mo; R = CH/sub 3/, C/sub 2/H/sub 5/) exhibit partial deprotonation of the water ligands leading to H/sub 3/O/sub 2//sup -/ bridges between M/sub 3/ clusters. EXAFS data did not distinguish monomers from polymers.