化学学报 ›› 2012, Vol. 70 ›› Issue (02): 107-113.DOI: 10.6023/A1109231    下一篇

研究论文

TTF-π 共轭桥-6-氧四联氮阳离子双自由基NLO性质的理论研究

李灼, 杜晓凤, 麻娜娜, 孙世玲, 仇永清   

  1. 东北师范大学化学学院 功能材料化学研究所 长春 130024
  • 投稿日期:2011-09-23 修回日期:2011-11-29 发布日期:2012-02-25
  • 通讯作者: 仇永清 E-mail:qiuyq466@nenu.edu.cn
  • 基金资助:

    国家自然科学基金(No.20873017);吉林省自然科学基金(No.20101154)资助项目

Theoretical Study on NLO Properties of TTF-π Conjugated Bridge-verdazyl Cation Diradicals

Li Zhuo, Du Xiaofeng, Ma Nana, Sun Shiling, Qiu Yongqing   

  1. Institute of Functional Material Chemistry, Faculty of Chemistry, Northeast Normal University, Changchun 130024
  • Received:2011-09-23 Revised:2011-11-29 Published:2012-02-25
  • Supported by:

    Project supported by the National Natural Science Foundation of China (No.20873017);and the Natural Science Foundation of Jilin Province (No.20101154).

采用量子化学UPBE1PBE 结合有限场(FF)方法, 对系列TTF-π 共轭桥-6-氧四联氮阳离子双自由基体系的稳定性, 极化率αs 和第一超极化率βtot 进行研究. 结果表明, TTF-6-氧四联氮阳离子双自由基引入共轭桥后, 随体系共轭性增强, αsβtot 值均增大(体系2S的βtot值除外). 自旋多重度和构象对双自由基体系的极化率和第一超极化率都有影响, 双自由基体系由单重态转变为三重态时, 极化率减小, 而第一超极化率明显增大. 以体系2为例, 在单重态时αsβtot值随构象变化较小, 而三重态时αsβtot值随二面角θ1θ2 的增加而减小.

关键词: 双自由基体系, 自旋多重度, NLO 性质, UPBE1PBE 方法

The stabilities, polarizabilities αs and the first hyperpolarizabilities βtot for a series of TTF-π conjugated bridge-verdazyl cation diradicals were investigated by using the UPBE1PBE method combined with the finite field (FF) approach. The results indicate that introducing conjugated bridges to TTF- verdazyl cation diradicals results in the conjugation of systems increasing, and then the αs and βtot values increasing (except for the βtot value of system 2S). The spin multiplicity and conformation both have influence on polarizability and the first hyperpolarizability. The polarizabilities of all systems decrease when the diradical systems change from singlet into triplet, while the first hyperpolarizabilities increase obviously. Taking the system 2 for example, the αs and βtot values change slightly with conformation in singlet, while the αs and βtot values decrease with increasing of the dihedral angle θ1 and θ2 in triplet.

Key words: diradical system, spin multiplicity, NLO property, UPBE1PBE method