Noble and Nonmagnetic Transition-Metal Clusters

Such a huge spin polarization is unusual in condensed systems, and would be extremely interesting if confirmed by experiments. 

DFT computations using localized basis functions have sporadically been applied to silver and gold microclusters. The early LSDA approach [226] (see Appendix C) to silver dimer and trimer (neutral and cationic) was a comparative study of results obtained with both le- and 11 e-pseudopotentials. It clarified the importance of the 4d-electron states in determining structural and bonding properties, which is partly related to their polarization. 

More recently, nonrelativistic all-electron GGA calculations were extended up to the silver hexamer [227] and used BP GC (see Appendix C). Some interesting discrepancies with the predictions of HF Cl calculations of Ref. [219] were found in particular the onset of 3D stable geometries at n = 6 was not confirmed. Although the full source 

In the case of gold, an attempt has been made to determine the convergence of several cluster properties, such as the cluster radius, the cohesive energy, the IP, and core-level shifts, with increasing size (up to n = 147) by means of AE-GGA (AE all-electron) calculations [228] (see Appendix C). The significance of the results is, however, marred by the fact that only selected, highly symmetric structures (icosahedra, cubo-octahedra and octahedra) were considered and that no structural relaxation beyond radial expansion was allowed. 

Of the family of nonmagnetic transition metals, niobium clusters are those for which most theoretical investigations have been made, although these were mainly restricted to the structural properties neutral clusters Nb , with n up to 7 (LDA [229]), with n = 8-10 (LDA [230, 231], LDA and B-LYP GC [223]), anionic clusters up to n = 8 (LDA [113]), anionic and cationic clusters with n = 8-10 (LDA and B-LYP GC [223]). Reference [223] (see Appendix C) presents an extensive structural study using CP molecular dynamics as well as local optimization procedures, and is corroborated by electronic and vibrational spectra as well as by an extension to cations and anions, thus allowing comparison 

---