Abstract
Recently developed density-functional-theory (DFT) and random-phase-approximation (RPA) methods are used to study competing isomers of some negatively charged Ta clusters, namely Ta12- and Ta10-, in an attempt to find a suitable strategy towards accurate studies of transition-metal clusters based on DFT. Also the neutral and cationic forms Ta12(0,+) of the twelve-atom cluster are studied. The results are compared with experimental information obtained by several methods that differ in the property under study and the total electric charge of the clusters. We find that a careful choice of the density functional, the use of relativistic two-component methods, eventually in combination with all-electron basis sets, and the application of RPA-type methods, may all be necessary steps for a good assessment. Such an assessment should be made in relation to several experimental properties as much as possible.
Acknowledgements
We thank Laurenz Monzel (Saarland University) and Christof Holzer (Karlsruhe Institute of Technology) for help with details of the computations with Turbomole. Our research was supported by the Bundesministerium für Bildung und Forschung (BMBF) through the Helmholtz Association via the PoF IV programme ‘Materials Systems Engineering' (MSE). JRF acknowledges support from the Xunta de Galicia by the GRC programme.
Disclosure statement
No potential conflict of interest was reported by the author(s).