title: Endohedral C3 Ca@B39(+) and C2 Ca@B39(+): axially chiral metalloborospherenes based on B39(-).
abstract: Using the newly discovered borospherenes C3 B39(-) and C2 B39(-) as molecular devices and based on extensive global-minimum searches and first-principles calculations, we present herein the possibility of the first axially chiral metalloborospherenes C3 Ca@B39(+) (, (1)A) and C2 Ca@B39(+) (, (1)A), which are the global minimum and the second lowest-lying isomer of CaB39(+), respectively. These metalloborospherene species turn out to be charge-transfer complexes Ca(2+)@B39(-) in nature, with the Ca centre on the C3 or C2 molecular axis donating one electron to the B39 cage which behaves like a superhalogen. Molecular orbital analyses indicate that C3/C2 Ca(2+)@B39(-) possess the universal bonding pattern of σ plus π double delocalization, similar to their C3/C2 B39(-) parents. Molecular dynamics simulations show that both C3 Ca@B39(+) () and C2 Ca@B39(+) () are dynamically stable at 200 K, with the former starting to fluctuate structurally at 300 K and the latter at 400 K, again similar to C3/C2 B39(-). The infrared and Raman spectra of C3/C2 Ca@B39(+) (/) are simulated and compared with those of C3/C2 B39(-) to facilitate their forthcoming experimental characterization.
authors.affiliation: Nanocluster Laboratory, Institute of Molecular Science, Shanxi University, Taiyuan 030006, China. luhg@sxu.edu.cn hj.zhai@sxu.edu.cn lisidian@sxu.edu.cn.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Chen
authors.forename: Ting
authors.initials: T
authors.lastname: Gao
authors.forename: Wen-Juan
authors.initials: WJ
authors.lastname: Tian
authors.forename: Hui
authors.initials: H
authors.lastname: Bai
authors.forename: Su-Yan
authors.initials: SY
authors.lastname: Zhang
authors.forename: Hai-Ru
authors.initials: HR
authors.lastname: Li
authors.forename: Chang-Qing
authors.initials: CQ
authors.lastname: Miao
authors.forename: Yue-Wen
authors.initials: YW
authors.lastname: Mu
authors.forename: Hai-Gang
authors.initials: HG
authors.lastname: Lu
authors.forename: Hua-Jin
authors.initials: HJ
authors.lastname: Zhai
authors.forename: Si-Dian
authors.initials: SD
authors.lastname: Li