New potential stable structures of <i>X</i> Mg <sub> <i>n</i> </sub> ( <i>X</i> <b>=</b> Ge, C, Sn; <i>n</i> <b>=</b> 2–12) clusters: <i>X</i> Mg <sub>8</sub> with high stability
Lu Zeng, Mei-Kun Liang, Xiaofan Wei, Jia Guo, Wei Dai, Ben‐Chao Zhu
Abstract
Abstract Several potential stable structures of X -doped magnesium ( X = Ge, C, Sn) clusters have been fully investigated by using CALYPSO structure searching software together with density functional theory calculations. X Mg n ( X = Ge, C, Sn; n = 3–7) clusters have similar geometric structure grows in tetrahedron, while the structures of X Mg n ( X = Ge, C, Sn; n = 8–12) are based on a kind of tower-like geometry. Interestingly, the relative stability computations indicate that X Mg 8 ( X = Ge, C, Sn) are more stable than other clusters, and thus can be identified as magic clusters. In addition, X Mg 8 's ( X = Ge, C, Sn) high stability and atomic interactions contained in structures are studied through their electronic localization function and molecular orbitals. It is shown that the covalent σ bond interaction of X –Mg and Mg–Mg are mainly responsible for their robust stability. Finally, the theoretical calculations of IR and Raman spectra of X Mg 8 ( X = Ge, C, Sn) clusters were implemented for guiding further experimental observation.