A computational study of vanadium peroxides (LnV(O-2)(m); m = 0-4), important for their biochemical and catalytic activity, is reported. In the compounds studied, ancillary ligands (L-n) are generally the hard, oxygen- and nitrogen-based donor ligands, e.g., carboxylates and pyridines, prevalent in the coordination chemistry of vanadium peroxides. The utility of estimating missing metal-dependent molecular mechanics (MM) parameters from quantum calculations is demonstrated. Given the limited vibrational data for many families of transition metal complexes, quantum calculations are a viable source for parameters to use in development of force fields. A conformational search of [V(O-2)(3)F](2-) using MM yielded a geometry inconsistent with experiment, but consistent with ab initio geometry optimizations. A reinvestigation of this structure is therefore of interest. Molecular mechanics provides a quick and accurate method for obtaining structural information. The level of agreement for structural prediction is competitive with that obtained using more computationally intensive methods in much less lime. In most cases it was seen that MM and quantum predictions reinforced each other, lending greater confidence in modeling results. In other cases, classical and quantum results were in conflict, indicating the need for further higher-level, quantum calculations. Hence, MM and low-level quantum calculations, when used together, provide a valuable method for quickly probing the conformational space of large coordination complexes.