Khemiri Noura, Abderrabba Manef, Messaoudi Sabri
Laboratoire Matériaux, Molécules et Applications, Institut Préparatoire aux Etudes Scientifiques et Techniques, La Marsa, Université de Carthage, Carthage, Tunisie.
J Mol Model. 2018 Sep 5;24(10):272. doi: 10.1007/s00894-018-3766-9.
A detailed theoretical study of the various possible fragmentation reactions of the benzophenone radical cation was carried out for the first time. In the first step, we optimized the geometries of all the structures resulting from the fragmentation of this cation using density functional theory (DFT). Our calculations were performed in the gas phase using the aug-cc-pVTZ basis set and the PBE1PBE functional. We determined the optimized structural parameters and the harmonic and anharmonic frequencies. The energies corresponding to all the optimized molecules were recalculated using the coupled cluster method CCSD(T). Upon comparing the fragmentation reaction energies, we found that the principal reaction was that leading to CHO and ·CH. We were able to theoretically demonstrate the existence of different fragments of the benzophenone cation: CO, CO·, ·CH, CH, ·CHO, CHO, biphenyl, and (biphenyl)·, and we found that the main products of the fragmentation reactions of the benzophenone cation are CHO and (biphenyl)·, which have been observed experimentally using slow photoelectron spectroscopy (SPES). Our theoretical results are in good agreement with the experimental results from benzophenone cation spectroscopy and fragmentation obtained using Benoît Soep's equipment at Synchrotron SOLEIL.
首次对二苯甲酮自由基阳离子的各种可能的碎片化反应进行了详细的理论研究。第一步，我们使用密度泛函理论（DFT）优化了该阳离子碎片化产生的所有结构的几何形状。我们的计算在气相中使用aug-cc-pVTZ基组和PBE1PBE泛函进行。我们确定了优化的结构参数以及谐波和非谐波频率。使用耦合簇方法CCSD(T)重新计算了所有优化分子对应的能量。通过比较碎片化反应能量，我们发现主要反应是生成CHO和·CH的反应。我们能够从理论上证明二苯甲酮阳离子存在不同的碎片：CO、CO·、·CH、CH、·CHO、CHO、联苯和（联苯）·，并且我们发现二苯甲酮阳离子碎片化反应的主要产物是CHO和（联苯）·，这已通过慢光电子能谱（SPES）实验观察到。我们的理论结果与使用同步加速器SOLEIL的Benoît Soep设备获得的二苯甲酮阳离子光谱和碎片化的实验结果高度一致。
