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As gold clusters increase in size, the preferred structure changes from planar to three-dimensional and, for anionic clusters, Aun-, the two-dimensional(2D)→three-dimensional (3D) transition is found experimentally to occur between n=11 and n=12. Most density functionals predict that planar structures are preferred up to higher n than is observed experimentally, an exception being the local spin density approximation. Here we test four relatively new functionals for this feature, in particular, M05, M06-L, M06, and SOGGA. We find that M06-L, M06, and SOGGA all predict the 2D→3D transition at the correct value of n. Since the M06-L and M06 functionals have previously been shown to be reasonably accurate for transition metal bond energies, main group atomization energies, barrier heights, and noncovalent interaction energies, and, since they are here shown to perform well for the s-d excitation energy and ionization potential of Au atoms and for the size of Aun- clusters at which the 2D→3D transition occurs, they are recommended for simulating processes catalyzed by gold clusters. [ABSTRACT FROM AUTHOR]

The CASPT2, CCSD, and CCSD(T) levels of wave function theory and seven density functionals were tested against experiment for predicting the ionization potentials and bond dissociation energies of actinoid monoxides and dioxides with their cations. The goal is to guide future work by enabling the choice of an appropriate method when performing calculations on actinoid-containing systems. We found that four density functionals, namely MPW3LYP, B3LYP, M05, and M06, and three levels of wave function theory, namely CASPT2, CCSD, and CCSD(T), give similar mean unsigned errors for actinoid-oxygen bond energies and for ionization potentials of actinoid oxides and their cations. [ABSTRACT FROM AUTHOR]