Singlet-triplet gaps in substituted carbenes predicted from block-correlated coupled cluster method  

作　　者：SHEN Jun FANG Tao LI Shuhua 

机构地区：[1]Key Laboratory of Mesoscopic Chemistry of Ministry of Education,Institute of Theoretical and Computational Chemistry,School of Chemistry and Chemical Engineering,Nanjing University,Nanjing 210093,China

出　　处：《Science China Chemistry》2008年第12期1197-1202,共6页中国科学（化学英文版）

基　　金：Supported by the National Natural Science Foundation of China (Grant Nos. 20625309 and 20433020);the National Basic Research Program (Grant No. 2004CB719901);the Ministry of Education of China (Grant No. NCET-04-0450); Fok Ying Tong Education Foundation (Grant No. 91014)

摘　　要：The block correlated coupled cluster (BCCC) method, with the complete active-space self-consistent-field (CASSCF) reference function, has been applied to investigating the singlet-triplet gaps in several substituted carbenes including four halocarbenes (CHCl, CF2, CCl2, and CBr2) and two hydroxycar-benes (CHOH and C(OH)2). A comparison of our results with the experimental data and other theoretical estimates shows that the present approach can provide quantitative descriptions for all the studied carbenes. It is demonstrated that the CAS-BCCC method is a promising theoretical tool for calculating the electronic structures of diradicals.The block correlated coupled cluster (BCCC) method, with the complete active-space self-consistent-field (CASSCF) reference function, has been applied to investigating the singlet-triplet gaps in several substituted carbenes including four halocarbenes (CHCl, CF2, CCl2, and CBr2) and two hydroxycarbenes (CHOH and C(OH)2). A comparison of our results with the experimental data and other theoretical estimates shows that the present approach can provide quantitative descriptions for all the studied carbenes. It is demonstrated that the CAS-BCCC method is a promising theoretical tool for calculating the electronic structures of diradicals.

关 键 词：BLOCK CORRELATED coupled cluster method CARBENE singlet-triplet gap DIRADICALS 

分 类 号：O621.2[理学—有机化学]