Conversions of localized excess electrons and spin states under external electric field: Inter‐cage electron‐transfer isomer ( C 20 F 20 ) 3 & K 2

By doping two potassium atoms among three C 20 F 20 cages, peanut‐shaped single molecular solvated dielectron (C 20 F 20 ) 3 &K 2 was presented theoretically. The triplet structure with two separated excess electrons respectively inside left and middle cages (isomers I or II ) are thermodynamically more stable than both open‐shell (OS) and close‐shell (CS) singlet ones with lone pair of excess electrons inside middle cage. Applying an oriented external electric field (×10 −4 au) of −20 or a larger one and then releasing it, left‐to‐right transfer occurs for both triplet excess electrons and a new kind of inter‐cage electron‐transfer isomers ( III or IV ) forms. Triplet structures ( I – IV ) with three redox sites may be new members of mixed‐valent compounds, namely, Robin‐Day Class II. For electrified I of (C 20 F 20 ) 3 &K 2 , the OS singlet state in small‐ranges of field strengths (−30 to −5 and 5–30), triplet one in mid‐ranges of field strengths (−120 to −30 and 30–111), and CS singlet one in large‐ranges of field strengths (≥111 and ≤−120) are, respectively, ground states.