Theoretical characteristics of the bound states of M-X complexes (M=Cu, Ag, and Au, and X=He, Ne, and Ar)

Abstract

The potential energy curves (PECs) of the bound states of M-X (M=Cu, Ag, and Au and X=He, Ne, and Ar) complexes have been calculated using the coupled cluster singles and doubles method with perturbative treatment of triple excitations. Large basis sets and bond functions, as well as the basis set superposition errors, are employed to obtain accurate PECs. The analytical potential energy functions (APEFs) are fitted using the PECs. The vibrational energy levels and the spectroscopic parameters for the complexes are determined using our APEFs and compared to the theoretical works available at present. We also find that the PECs are bound with similar van der Waals interactions, which implies that He, Ne, and Ar may be used for buffer-gas cooling; and Cu, Ag, and Au may be trapped with a similar method because Cu and Ag have been experimentally trapped with He buffer-gas cooling.

A Systematic Search for Structures, Stabilities, Electronic and Magnetic Properties of Silicon Doped Silver Clusters: Comparison with Pure Silver Clusters

“…For the lowest energy of the Ag n Si (n = 1 -9) clusters, the HOMO-LUMO gaps for the most stable Ag n Si and Ag n+1 clusters against the cluster size are plotted in Figure 3. The trend of the Ag n Si and Ag n+1 clusters show a contrary odd-even oscillation similar to ∆E(n) and ∆ 2 E(n), which implies that Ag 2,4,6,8 Si and Ag 3,5,7,9 clusters have an enhanced stability compared with their neighbour clusters. Interestingly, the significant peak is also localized at n = 4 and the Ag 4 Si isomer has the largest HOMO-LUMO gap of 2.54 eV.…”

“…(ii) By analyzing the relative stabilities of the Ag n Si (n = 1 -9) clusters, we found that the Ag 4 Si isomer shows the strongest stability due to its local peak in all the curves of E b (n), ∆E(n), ∆ 2 E(n), E dis (n), and HOMO-LUMO gaps. The HOMO-LUMO gaps show a contrary odd-even oscillation, which implies that Ag 2,4,6,8 Si and Ag 3,5,7,9 clusters have enhanced stability compared with their neighbours. (iii) The charges in Ag n Si (n = 1 -9) clusters transfer from the Ag n frames to the silicon atom.…”

“…Firstly, for the total magnetic moments of the Ag n Si (n = 1 -9) clusters exist distinctly odd-even alternation behaviours. For Ag 1,3,5,7,9 Si clusters, the total magnetic moment is close to 1µ B whereas for Ag 2,4,6,8 Si clusters, the values are zero. Secondly, the local magnetic moments from the silicon atoms and the Ag n frames in corresponding Ag n Si clusters shown the same odd-even behaviour.…”

“…From Table 2, one can see that 7a is a little more stable than the 7b and 7c isomers; the energy differences are 0.003 eV. Taking the energy gaps into account, 7a can be viewed as the most stable structure of Ag 7 Si clusters. In the case of ground states, isomer 8a can be described as one silver atom being right-capped on the 7b structure and also viewed as one silver atom being left-capped on the 7c cluster.…”

Energetics of pure and doped helium droplets - application to interpreting pick-up experiments

“…Once again, the dopant-helium interaction enters the functional as V external , but now has the form suggested by Tong et al 22 …”