作　　者： ; ; ;

机构地区： 华南理工大学

出　　处： 《分子科学学报》 2014年第1期75-80,共6页

摘　　要： 在6-31G(d,p)水平上用B3LYP方法对三苯基corrole(TPC)以及氟苯基corrole系列分子进行几何构型优化.用ZINDO/SOS方法计算了这些分子的一阶超极化率.计算结果表明:TPC分子由于其结构非中心对称使其具有大小为2.46×10-50 C3·m3·J-2的一阶超极化率.引入氟苯基后,氟取代苯基corrole系列分子的一阶超极化率均有显著提高,其中5位及10,15位氟苯基取代的corrole分子具有较大的一阶超极化率(3.71×10-49 C3·m3·J-2).氟苯基corrole系列分子一阶超极化率提高主要起源于分子的二能级分量及三能级分量显著增大,且二能级分量与三能级分量大小相当、符号相同.计算表明,二能级分量的增大主要来源于第三激发态(B1)与基态之间的偶极矩的变化.跃迁通道分析表明三能级分量的增大主要通过改变与结构敏感的激发态跃迁通道,即由TPC分子B带与Q带的耦合变成了氟苯基corrole分子B带内2个不同激发态的耦合. The geometries of tri phenylcorrole （TPC） and a series of pentafluorophenyl substituted cor- roles were optimized using B3LYP method at 6 31G（d,p） basis set level. First hyperpolarizabilities of these corroles were calculated using the ZINDO/SOS method. Calculation results showed that the first hyperpolarizability of tri-phenylcorrole （TPC） was of moderate value （2.46× 10^-50 C3· m3· J-2） due to its nonsymmetrical geometry structure. The first hyperpolarizabilities of pentafluorophenyl substi tuled corrole increased significantly and varied to the position of substituents. 5-phenyl-10,15- di（pen tafluorophenyl）corrole showed the largest first hyperpolarizabilities （3.71 × 10^-49C3·m3·J-2）. The enhancement of first hyperpolarizabilities of pentafluorophenyl substituted corrole originated from the dramatically increasing of their three-level components which are of the same sign and size with the two level contributions. Our calculations implied that, the stronger two level contributions were due to the transition dipole moments between the ground and the third excited states （B1）. Transition channel analysis showed that the increasing of three-level components was caused by changing the piv oral transition channel of exited states, which are sensitive to the structure, from coupling between B and Q bands in TPC to the coupling between two different exited states of B band in pentafluorophenyl substituted corrole.

关 键 词： 取代基 一阶超极化率 偶极矩 跃迁通道

领　　域： [理学] [理学]