AM1/d Parameters for Molybdenum

The AM1 scheme extended to d orbitals, AM1/d, has been parametrized for molybdenum. Computational results on structures and energetics of a series of molybdenum compounds are compared with experimental data. The mean absolute error of bond lengths is 0.044 Å (83 comparisons) and that of X-Mo-Y angles is 3.3° (65 comparisons). The mean absolute error of heats of formation amounts to 6.5 kcal/mol (50 comparisons). This assessment demonstrates the good performance of AM1/d. Thus, the proposed method may be used for computing structural parameters as well as heats of formations, reaction enthalpies, and bond energies of rather large inorganic and organometallic compounds of molybdenum.