text: Many metal alkoxide compounds also feature oxo-ligands. Oxo-ligands typically arise via the hydrolysis, often accidentally, and via ether elimination:
  Additionally, low valent metal alkoxides are susceptible to oxidation by air.
  Characteristically, transition metal alkoxides are polynuclear, that is they contain more than one metal.  Alkoxides are sterically undemanding and highly basic ligands that tend to bridge metals.
  Upon the isomorphic substitution of metal atoms close in properties crystalline complexes of variable composition are formed. The metal ratio in such compounds can vary over a broad range. For instance, the substitution of molybdenum and tungsten for rhenium in the complexes  allowed one to obtain complexes  in the range  and  in the range .