The Possible Superalkali Clusters Lin+1Fn (n = 2 ~ 17)

• Published in: Journal of cluster science 2024, Vol.35 (1), p.55-67
• Main Authors: Yin, Yue-Hong, Liu, Wen-Juan
• Format: Article
• Language: English
• Subjects: Bonding strength; Catalysis; Chemistry; Chemistry and Materials Science; Clusters; Configurations; Electronic structure; Electrons; Energy; Genetic algorithms; Inorganic Chemistry; Investigations; Ionization potentials; Isomers; Nanochemistry; Neutrons; Optics; Original Paper; Physical Chemistry; Planar structures; Spectrum analysis; Structural analysis
• ISSN: 1040-7278; 1572-8862
• DOI: 10.1007/s10876-023-02461-4

Using a genetic algorithm together with DFT computations, the stable isomers of Li n +1 F n ( n  = 2 ~ 17) are obtained. It is found that the Li 3 F 2 is a planar structure, and starting at n  = 3, Li n +1 F n adopt three-dimensional configurations with a terminal Li atom or vacancy of F atom. As the cluster sizes increase, the geometries of Li n +1 F n develop, first with cube-like and tubular structures, then forming cage-like arrangements, and eventually favoring rock-salt configurations. The Li n +1 F n ( n  = 3, 5, 8, 11, 13 and 15) are especially stable and magic number clusters. Low ionization potentials are acquired for Li n +1 F n due to the weakly bonded odd electrons of Li atoms. Particularly, the AIP/VIP for Li 14 F 13 and Li 17 F 16 are only 2.68/2.75 eV and 2.77/2.97 eV, respectively, which indicate that they can be looked as superalkali clusters. Meanwhile, the particularly large hyperpolarizabilities (3237157.14 a.u. and 716489.10 a.u.) for these two isomers are also obtained. According to the electronic structure analysis, Li atoms donate their 2s electrons to the 2p orbitals of F atoms, forming Li–F ionic bonds. Additionally, the spectral properties and the reactivities for the magic number clusters are further investigated.