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A new kind of cationic superatom compounds (M-F)(+) (M = OLi4, NLi5, CLi6, BLi7, and Al14) with low vertical electron affinities (VEA) has been designed based on the distinctive electronic structure of superalkaline-earth atom. The stability of the studied superatom architectures is guaranteed by strong M-fluorine interactions, considerable HOMO-LUMO gaps, as well as large dissociation energies. What is extraordinary is that fluorination plays an important role in lowering the VEA value of M(+) and enables the resulting (M-F)(+) fluorides to join the superalkali family. However, the same strategy does not work as well for the alkaline-earth atoms whose valence electrons are more tightly bound. The comparative study on (OLi4-X)(+) (X = F, Cl, Br) reveals that fluorination is more effective than chlorination and bromination to reduce the VEA value of the OLi4(+) cation. As for the (Al14-X)(+) species, there is no obvious dependence of VEA values on halogen atomic number.

The structures and nonlinear optical properties of a novel class of alkali metals doped electrides B 12 N 12 -M (M 5 Li, Na, K) were investigated by ab initio quantum chemistry method. The doping of alkali atoms was found to narrow the energy gap values of B 12 N 12 in the range 3.96-6.70 eV. Furthermore, these alkali metals doped compounds with diffuse excess electron exhibited significantly large first hyperpolarizabilities (b 0 ) as follows: 5571-9157 au for B 12 N 12 -Li, 1537-18,889 au for B 12 N 12 -Na, and 2803-11,396 au for B 12 N 12 -K. Clearly, doping of the alkali atoms could dramatically increase the b 0 value of B 12 N 12 (b 0 5 0). Furthermore, their transition energies (DE) were also calculated. The results showed that these compounds had low DE values in the range 1.407-2.363 eV, which was attributed to large b 0 values of alkali metals doped B 12 N 12 nanocage.

On the basis of stable all‐cis 1,2,3,4,5,6‐hexafluorocyclohexane, a series of alkali metal atom doped MF6C6H6 (M = Li, Na, and K) compounds were theoretically constructed and studied by using ab initio quantum chemistry method. The calculated results show that the HOMO–LUMO gap of the MF6C6H6 conspicuously narrowed from 10.41 eV of pure F6C6H6 to about 2.00 eV of MF6C6H6. The electride characteristics of MF6C6H6 are verified by their electronic structures, HOMOs, and small VIE values. As expected, these electrides possess considerable static first hyperpolarizabilities (β0). Among the studied electrides, the largest β0 of the LiF6C6H6 is 7.00 × 105 au, which is about 3030 times larger than pure F6C6H6. TD‐M06‐2X calculations show that these larger β0 values are attributed to lower transition energies for the crucial excited states of MF6C6H6 systems. Further, the vibrational contributions to the static first hyperpolarizabilities of these molecules are also estimated. Moreover, Li atom doped dimer and trimer of F6C6H6 also present unusual electride's features and exhibit dramatically large β0. Thus, the F6C6H6 interacting with the alkali metal atoms may be a potential promising NLO nanomaterial.