Wang Jia-Jun, Zhou Zhong-Jun, Bai Yang, He Hui-Min, Wu Di, Li Ying, Li Zhi-Ru, Zhang Hong-Xing
State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun, 130023, China.
Dalton Trans. 2015 Mar 7;44(9):4207-14. doi: 10.1039/c4dt03282a.
Novel cup-saucer-cage-shaped sandwich electride molecules calix[4]pyrrole···K3O(+)···e@C(n)F(n)(-), (n = 8, 10, 14, 20, and 36) with an excess electron protected inside the C(n)F(n) cage are constructed theoretically. In the sandwich structures, the below calix[4]pyrrole cup pushes the valence electron of the sandwiched superalkali atom K3O saucer, forming an excess electron, which is further pulled and protected inside the above C(n)F(n) cage, thus an electron-transfer relay occurs. In particular, owing to the unusual electron transfer, an unusual and fortunate phenomenon is discovered that increasing the C(n)F(n) cage size enhances not only the nonlinear optical response (β0), but also the electron stability (VIP). Thus, a new strategy of simultaneously enhancing β0 and VIP values is found for the first time, namely by increasing the C(n)F(n) cage size in novel cup-saucer-cage-shaped sandwich electride molecules, with the excess electron protected inside the cage.
理论上构建了新型杯-碟-笼状夹心电子化物分子杯[4]吡咯···K₃O⁺···e@CₙFₙ⁻（n = 8、10、14、20和36），其中一个多余电子被保护在CₙFₙ笼内。在夹心结构中，下方的杯[4]吡咯杯推动被夹在中间的超碱原子K₃O碟的价电子，形成一个多余电子，该多余电子被上方的CₙFₙ笼进一步吸引并保护起来，从而发生电子转移中继。特别地，由于这种不寻常的电子转移，发现了一种不寻常且幸运的现象，即增大CₙFₙ笼的尺寸不仅增强了非线性光学响应（β₀），还增强了电子稳定性（VIP）。因此，首次发现了一种同时提高β₀和VIP值的新策略，即在新型杯-碟-笼状夹心电子化物分子中增大CₙFₙ笼的尺寸，同时将多余电子保护在笼内。
