A systematic search for the structures, stabilities, and electronic properties of bimetallic Ca2-doped gold clusters: comparison with pure gold clusters

Abstract

The local meta-GGA exchange correlation density functional (TPSS) with a relativistic effective core potential was employed to systematically investigate the geometric structures, stabilities, and electronic properties of bimetallic Ca(2)Au( n ) (n = 1-9) and pure gold Au( n ) (n ≤ 11) clusters. The optimized geometries show that the most stable isomers for Ca(2)Au( n ) clusters have 3D structure when n > 2, and that one Au atom capping the Ca(2)Au( n-1) structure for different-sized Ca(2)Au( n ) (n = 1-9) clusters is the dominant growth pattern. The average atomic binding energies and second-order difference in energies show that the Ca(2)Au(4) isomer is the most stable among the Ca(2)Au( n ) clusters. The same pronounced even-odd alternations are found in the HOMO-LUMO gaps, VIPs, and hardnesses. The polarizabilities of the Ca(2)Au( n ) clusters show an obvious local minimum at n = 4. Moreover, the inverse corrections to the polarizabilities versus the ionization potential and hardness were found for the gold clusters.

Aun (n = 1,11) Clusters Interacting With Lone-Pair Ligands

“…Passing from the single gold atom to Au n clusters and their interactions with closed-shell ligands, we should realize that electronic properties of gold clusters heavily depend on the cluster size and its structure. Most stable neutral Au n clusters exhibit odd–even oscillations of EAs, IPs, mean polarizabilities per atom, HOMO–LUMO gaps, ,, or also the number of peaks in the photoelectron spectra . These properties only slowly converge to the bulk values.…”

Evolution of structures, stabilities, and electronic properties of anionic [AunRb]−(n= 1–10) clusters: comparison with pure gold clusters

“…For Au and Rb atoms, full electron calculation is rather time-consuming, so it is better to introduce effective core potential Lanl2Dz basis set [40][41][42] to describe the outermost valence electrons. In searching for the lowest energy structures, lots of possible initial structures, which include 1D, 2D, and 3D configurations, are considered starting from the previous optimised Au n − and [XAu n ] − geometries [6][7][8][9][11][12][13][14][15][18][19][20][21][22][23] and all clusters are relaxed fully without any symmetry constraints. Towards nuclear displacement, all the structures have real vibrational frequencies and therefore correspond to the potential energy minima.…”

“…Recently, the gold-based clusters have attracted considerable attention due to their particular physical and chemical properties as well as technological applications in catalysis, biology, nanoscale devices, materials science, and medicine [1][2][3][4][5]. Therefore, a great number of experimental and theoretical works about impurity-doped or mixed gold clusters have been performed [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23].…”

Rapid 3D roll-up of gas-phase planar gold clusters and affinity and alienation for Mg and Ge: A theoretical study of MgGeAun (n=1–12) clusters

“…( Arratia-Perez et al., 1989 ), Zhao et al. ( Zhao et al., 2012a ), Shao et al. ( Shao et al., 2012 ), and Sui et al.…”

“…The study of doped gold clusters with two same atoms has also been studied, for example, Ca 2 Au n , Be 2 Au n , Cu 2 Au n , Ag 2 Au n , Si 2 Au n , P 2 Au n , Na 2 Au n , Mg 2 Au n . and Al 2 Au n showing that the ground state structures from Ca 2 Au 3 ( Zhao et al., 2012a ), Be 2 Au 5 ( Zhao et al., 2012b ), Cu 2 Au 6 and Ag 2 Au 6 ( Zhao et al., 2011 ), Si 2 Au 2 , P 2 Au 3 , ( Li et al., 2012 ), Na 2 Au 2 , Mg 2 Au 4 and Al 2 Au 2 ( Li et al., 2013 ) are no longer planar. Moreover, the effect of such two same kinds of atom doping on the planar structure is sometimes discontinuous, i.e., Be 2 Au 5 , Cu 2 Au 6 , and Ag 2 Au 6 are 3D structures, but Be 2 Au 6 , Cu 2 Au 7 , Ag 2 Au 7 revert to planar geometry.…”