Buckyball Difluoride F-2(-)@C-60(+)-A Single-Molecule Crystal

0495279 - ÚOCHB 2019 RIV DE eng J - Journal Article
Foroutan-Nejad, C. - Straka, Michal - Fernandez, I. - Frenking, G.
Buckyball Difluoride F-2(-)@C-60(+)-A Single-Molecule Crystal.
Angewandte Chemie - International Edition. Roč. 57, č. 42 (2018), s. 13931-13934. ISSN 1433-7851. E-ISSN 1521-3773
R&D Projects: GA ČR(CZ) GA17-07091S
Institutional support: RVO:61388963
Keywords : bonding analysis * DFT calculations * endohedral fullerenes * fluorine * molecular crystals
OECD category: Physical chemistry
Impact factor: 12.257, year: 2018

We report the F-2@C-60 system as the first example of an endohedral fullerene in which C-60 acts as a cation C-60(+) interacting with endohedral anion, F-2(-). Our state-of-the-art computations reveal that in F-2@C-60, despite of the known high electron affinity of C-60, an electron is transferred from C-60 to F-2 resulting in the F-2(-)@C-60(+) system. The F-F bond length in F-2@C-60 is substantially longer than in free F-2, which is the result of electron-transfer to the antibonding sigma(u) molecular orbital of F-2. Interestingly, although there is a full charge-transfer of one electron between C-60 and F-2, only negligible delocalized covalent interactions are found between F-2(-) and C-60(+) which is a reminiscent of ionic crystals. Therefore, F-2(-)@C-60(+) can be considered as a single-molecule crystal. The other encapsulated halogens in C-60 do not show such behavior.
Permanent Link: http://hdl.handle.net/11104/0288877