C_nH_(2n+1)O_2·/C_nH_(2n+1)O_2^-(n=1～4)的结构和电子亲合能的密度泛函理论研究

Study on structures and electron affinities of the C_nH_(2n+1)O_2·/C_nH_(2n+1)O_2^-(n=1～4) with density functional theory

选用4种不同的密度泛函理论方法(B3LYP,BHLYP,BP86,BPW 91),在全电子的双ζ加极化加弥散函数基组(DZP++)下,研究CnH2n+1O2./CnH2n+1O2-(n=1~4)体系的结构和电子亲合能。预测过氧烷基自由基及相应的阴离子的基态结构均为Cs对称性,电子态分别为2A″和1A′。在电子亲合能方面,BP86方法预测的电子亲合能是最可靠的。预测CH3O2.,C2H5O2.,a-C3H7O2.,b-C3H7O2.,a-C4H9O2.和b-C4H9O2.的电子亲合能分别为1.15,1.12,1.13,1.10,1.11和1.18 eV。

Four different density functional theory （DFT） methods （B3LYP, BHLYP, BP86, and BPW91） had 1Seen employed to predict the radical structures and adiabatic electron affinities of the CnH2n＋1 O2·/CnH2n＋1 O2^-（n=1～4） species. The basis set was of double-ζ plus polarization quality with additional s- and p-type diffuse functions, labeled as DZP ＋＋. The ground states of CnH2n＋1 O2·/CnH2n＋1 O2^-（n=1～4） were the Cs symmetry. The electron state of the radicals and corresponding anions were ^2A′ and ^1A′, respectively. The BP86 in all of these schemes were the best in respect of predicting electron affinities. The electron affinities corrected by zero-point vibrational energies for CH3O2· , C2H5O2· , a-C3H7O2· ,b-C3H7O2· ,a-C4H9O2· and b-C4H9O2· were 1. 15, 1.12, 1.13, 1.10, 1.11 and 1.18 eV, respectively.