Probing the effects of lithium doping on structures, properties, and stabilities of magnesium cluster anions

Bimetallic clusters have aroused tremendous interest because the property changes like structure, size, and composi-tion have occurred. Herein, a structural search of the global minimum for anionic LiMgn- (n = 2-11) clusters is performed using an efficient crystal structure analysis by particle swarm optimization (CALYPSO) structural searching program with subsequent density functional theory (DFT) calculations. A great variety of low energetic isomers are converged, and the most stable ones are confirmed by comparing their total energy of each size. It is found that the LiMg(n )(-)clusters are structurally consistent with corresponding Mg clusters anions except for LiMg-5 and LiMg-7 . In all the doped clusters, the Li atom prefers to occupy the convex position. Simulated photoelectron spectra (PES), Infrared (IR), and Raman spectra of LiMgn- could be used as an essential evidence for identifying cluster structures experimentally in the future. Stability study reveals that a tower-like structure of LiMg- 9 has prominent stability and can be identified as a magic number cluster. The reason might be that there are both closed-shell 1S(2)1P(6)1D(10)2S(2) electronic configurations and stronger Li-Mg bonds caused by sp hybridization in the LiMg- (9) cluster.