非对称笼间电子迁移异构体与电场诱导电子迁移

基于密度泛函理论研究了非对称双笼型单分子溶剂化电子e^-@C₂₄F₂₂(NH)₂C₂₀F₁₈(1、2 和3), 进一步展示了我们提出的一种新型电子异构体——(非对称型的)笼间电子迁移异构体. 1、2 和3 具有显著不同的偶极矩. 由于都存在两个氧化还原中心, 它们属于一种非金属型的新型Robin-Day II-III 分子. 对于1 和3, 额外电子分别定域在C₂₄F₂₂和C₂₀F₁₈笼里(Robin-Day II); 对于2, 额外电子则离域于两个非对称的笼中(Robin-Day III). 值得注意的是, 在y 轴方向上外加-0.0004和-0.0008 a.u.的临界电场(E_c)时可分别使1 的额外电子从C₂₄F₂₂笼中部分和全部地迁移到C₂₀F₁₈笼中, 即实现从1 到2 再到3 的转化; 当E_c为0.0004 a.u.时, 3 的额外电子从C₂₀F₁₈笼中全部迁移到了C₂₄F₂₂笼中, 即3 未经过2 直接转化成了1.

Asymmetrical Inter-Cage Electron Transfer Electromers and Their Transfer Characteristics Under Electric Fields

The asymmetrical, double-cage-shaped, single molecular solvated electron compounds e^-@C₂₄F₂₂(NH)₂C₂₀F₁₈ (1, 2, and 3) were investigated based on density functional theory (DFT). This work revealed a novel species of electromer consisting of asymmetrical inter-cage electron-transfer isomers. These inter-cage electron-transfer isomers belong to a new form of Robin-Day class II-III molecules. 1 and 3 are Robin-Day class II, with the excess electron inside the C₂₄F₂₂ and C₂₀F₁₈ cages respectively, while 2 is class III with the excess electron inside both cages. These electromers were found to exhibit significantly different dipole moments. The application of external electric fields of -0.0004 or -0.0008 a.u. in the y-axis direction of 1 resulted in either partial or whole transfer of the excess electron from C₂₄F₂₂ to C₂₀F₁₈, allowing conversion from 1 to 2 or 3. An E_c value of 0.0004 a.u. was determined, indicating that the excess electron can wholly transfer from the C₂₀F₁₈ cage to C₂₄F₂₂, resulting in conversion from 3 to 1 without going through 2.