25. Why is X-ray crystallography not useful for the characterization of transition metal dihydrogen complex? Name at least two other methods that are useful and briefly elaborate. (10%)

21. Consider the octahedral vanadyl ion, VO(H2O)5^2+: (15%) (a) First, construct the molecular orbital diagram of square pyramidal V(H2O)5^4+. Assume that H2O is a pure σ donor. Provide an appropriate label for each molecular orbital, sketch each molecular orbital, and fill in the correct number of electrons. (6%)