Structural and spectral properties of a non-classical C₅₈ isomer and its fluorinated derivatives in theory

Abstract

The X-ray spectra have good isomer dependence and give a comprehensive insight of the electronic structure of the system.

Structural and Spectral Properties of a Nonclassical C66 Isomer with Its Hydrogenated Derivative C66H4 in Theory

“…Furthermore, by comparing the total spectra before and after hydrogenation, as well as their type-specific contributions in all figures, one can easily find a distinct blue shift of about 5.0 eV for DFP and TSFP sites after hydrogenation in comparison to spectra of the other carbon atoms. According to the previous NEXAFS chlorides and fluorides, , the blue shift is about 5.0–6.0 eV, which is similar to the NEXAFS spectra of hydrides in this work. Consequently, the NEXAFS spectra created by the hydrogenated derivatives are visibly different from those of the corresponding parent fullerenes, effectively reflecting the changes in the electronic structure of the carbon cages after hydrogenation.…”

“…Analyzing the spectra of pure cages and hydrides, it is not difficult to discover that after hydrogenation, the TSFP and DFP sites directly connected to hydrogen atoms have a blue shift of approximately 1.0 eV. Comparing with the previous XPS studies on chlorides and fluorides, 20,30 for which the fused pentagon sites have an enhancement of about 2.8−4.0 eV, the blue shift is much smaller. This phenomenon may result from the fact that the binding energy of carbon 1s electrons will increase differently depending on the bond type of fused-pentagon carbon atoms.…”

“…The spectra of the hydrogen derivatives also confirmed this observation. According to the previous studies, 29,30 it can be reasonably predicted that as the abundance of the fused pentagon sites increases, the contribution to the spectrum will be greater and the features will be more obvious.…”

“…These results are consistent with the previous simulation of Xray photoelectron spectra of C 54 , 27 C 74 , 28 C 78 29 , and C 58. 30 . Figure 4 presents the calculated X-ray photoelectron spectra of the three corresponding C 66 hydrogenated derivatives and the spectral contributions generated by different types of carbon atoms.…”

“…Besides, a further investigation into the electronic structures and spectroscopic properties by X-ray methods would be beneficial to gain a deeper comprehension in many respects. These techniques are widely used in the qualitative analysis of compounds and have been used to identify the electronic structures of many molecules, surfaces, or bulk materials, such as fullerenes, DNAs, carbon nanotubes, and so forth. − Quite a few X-ray spectroscopy calculations for the identification of fullerene isomers and their derivatives have been completed successfully, such as C 54 , C 74 , C 78 , C 58 , C 60 , and C 72 . X-ray photoelectron spectroscopy (XPS) provides the information of the core orbital by ionization of nuclear electrons, while near-edge X-ray absorption fine structure (NEXAFS) gives the features of virtual orbitals through excitation of core electrons to virtual orbitals.…”