五元杂环分子超极化率的电子相关效应  

Electron Correlation Effects in the Hyperpolarizabilities of Five-membered Heterocyclics

作　　者：王煦[1] 杨明理[2] 孙泽民[2] 

机构地区：[1]西南石油学院化工系,南充637001 [2]四川大学化学学院,成都610064

出　　处：《高等学校化学学报》2001年第2期257-261,共5页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金!(批准号 :2 970 6 115 )资助

摘　　要：用有限场方法在H F和MP4水平上计算呋喃、吡咯和噻吩的极化率、一阶和二阶超极化率 .结果表明 ,电子相关效应对各阶极化率 ,尤其是高阶极化率影响较大 .MP2计算值较H F有显著改善 ,一阶超极化率的MP2 ,MP3和MP4计算值依次增大 ,二阶超极化率的MP2和MP4值相近 ,而MP3值小于MP2 .呋喃、吡咯和噻吩的各阶极化率在各级微扰中均具有与H F水平上一致的相对大小顺序 .The dipole moments, polarizability, first- and second-order hperpolarizabities of pyrrole, furan and thiophene have been calculated by finite-field method at Hartree-Fork and Mller-Plesset levels, respectively. The calculation shows that electron correlation effects have considerable influences on the polarizability at all orders, in particular the high-order ones. The MP2 calculation improves the results remarkably at H-F level. The first-order hyperpolarizabilities increase in the order of MP2, MP3 and MP4, while the second-order hyperpolarizabilities at MP2 level are similar to those at MP4 level and are larger than those at MP3 level. The same relative order of the all-order polarizability is found between H-F level and different orders of Mller-Plesset method.

关 键 词：五元杂环分子 超极化率 电子相关效应 有限场方法 吡咯 呋喃 噻吩 

分 类 号：O626.1[理学—有机化学] O641.12[理学—化学]