Differences in electronic properties of fluorinated and trifluoromethylated fullerenes revealed by their propensity for dianion formation

Abstract

The cross sections for electron transfer from sodium to C(60)F(n) (-) and C(60)(CF(3))(n) (-) anions in 50-keV collisions as a function of the number of functional groups n are reported. There are clear differences between derivatives of fluorine and trifluoromethyl due to the different electron withdrawing properties of F and CF(3). The role of inductive effects and pi electron delocalization on the electron affinity is discussed, assuming a correlation between the cross section and the electron affinity of the anion.

Electrochemical, Spectroscopic, and DFT Study of C60(CF3)n Frontier Orbitals (n = 2−18): The Link between Double Bonds in Pentagons and Reduction Potentials

“…The B3LYP-predicted EA (2) values for some of the C 60 (CF 3 ) n compounds are positive, which indicates that their dianions should be stable species in the gas phase. Indeed, C 60 (CF 3 ) n 2- ( n = 2−20) dianions were generated recently by collisions of the corresponding monoanions produced in an electrospray ion source with sodium atoms . Cross sections for electron capture by monoanions decreased on going from n = 10 to n = 20.…”

Probing the intrinsic features and environmental stabilization of multiply charged anions

“…As the excess charge increases, the ion will become less stable with respect to both electron loss and ionic fragmentation. 37,38,59,60 However, more highly charged ions will be particularly prone to decay via spontaneous electron loss due to rapid electron tunnelling. Some direct experimental evidence for the intrinsic instability of small molecular trianions has been provided by novel experiments exploring electron scattering of a corresponding dianion, e.g.…”

Energy-dependent gas-phase fragmentation of fluorofullerene multiply charged anions (MCAs)

“…[1][2][3][4] Stable gas phase dianions of fluorofullerenes have long been known and have been the topic of several investigations. [5][6][7][8][9][10][11][12][13][14] Fluorofullerene dianions have been generated in various ways, including double electron attachment, 5,14 electrochemical production followed by electrospray ionization-based transfer into the gas phase, 13 electrospray ionization (ESI) from solutions doped with organic electron donor compounds, 6,8 direct ESI 9 and high-kinetic energy collisions, causing electron transfer to a monoanionic projectile fluorofullerene ion from gaseous sodium 7 and other gases. [10][11][12] In the latter experiments it has been even possible to generate long-lived fluorofullerene trianions.…”