CAJ | 학술논문

采用全活化空间自洽场方法(CASSCF)在C_2v对称性和ANO-S基组水平下, 研究了H_2CCC自由基及其阴阳离子的基态和低激发态性质. 为了进一步考虑动态电子相关效应, 采用多组态二级微扰理论(CASPT2)获得了更加精确的能量值. 计算得到X~1A_1 → ~1A_2, X~1A_1 →~ 1B_1和X~1A_1 → 2~1A_1在159.0, 216.5和476.4 kJ/mol处的激发可分别归因于π(b_2)→π~*(b_1), n(a_1)→π~*(b_1)和π(b_1)→π~*(b_1)的跃迁, 理论波长与紫外吸收光谱得到的实验数据一致. 计算得到的电子亲和势与实验值也非常接近.
채용전활화공간자흡장방법(CASSCF)재C_2v대칭성화ANO-S기조수평하, 연구료H_2CCC자유기급기음양리자적기태화저격발태성질. 위료진일보고필동태전자상관효응, 채용다조태이급미우이론(CASPT2)획득료경가정학적능량치. 계산득도X~1A_1 → ~1A_2, X~1A_1 →~ 1B_1화X~1A_1 → 2~1A_1재159.0, 216.5화476.4 kJ/mol처적격발가분별귀인우π(b_2)→π~*(b_1), n(a_1)→π~*(b_1)화π(b_1)→π~*(b_1)적약천, 이론파장여자외흡수광보득도적실험수거일치. 계산득도적전자친화세여실험치야비상접근.
Complete active space self-consistent field(CASSCF) calculations with ANO-S basis sets were performed for a few electronic states of propadienylidene, H_2CCC, and its cation and anion in C_2v symmetry. For all the calculated states, the accuracy of the total energies was improved by including dynamic electron correlation via the multiconfiguration second-order perturbation theory(CASPT2) method. The results suggest that the calculated transitions of X~1A_1 → ~1A_2, X~1A_1 →~ 1B_1 and X~1A_1 → 2~1A_1 at 159.0, 216.5 and 476.4 kJ/mol are attributed to π(b_2)→π~*(b_1), n(a_1)→π~*(b_1) and π(b_1)→π~*(b_1) transition, respectively. The electron affinities were obtained in comparison with the photoelectron spectrum(PES) data. These above results are in agreement with the previous experimental data.