物理化学学报 >> 2014, Vol. 30 >> Issue (7): 1223-1229.doi: 10.3866/PKU.WHXB201405091

理论与计算化学 上一篇    下一篇

碱金属掺杂叔丁基杯[4]芳烃体系的结构及非线性光学性质

侯娜, 李莹, 吴迪, 李志儒   

  1. 吉林大学理论化学研究所, 理论化学计算国家重点实验室, 长春 130023
  • 收稿日期:2014-01-24 修回日期:2014-05-08 发布日期:2014-06-30
  • 通讯作者: 吴迪 E-mail:wud@mail.jlu.edu.cn
  • 基金资助:

    国家自然科学基金(21173095,21173098,21303066)资助项目

Structures and Nonlinear Optical Properties of Alkali Metal-Doped t-Bu-calix[4]arene Molecules

HOU Na, LI Ying, WU Di, LI Zhi-Ru   

  1. State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun 130023, P. R. China
  • Received:2014-01-24 Revised:2014-05-08 Published:2014-06-30
  • Contact: WU Di E-mail:wud@mail.jlu.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21173095, 21173098, 21303066).

摘要:

采用密度泛函理论B3LYP方法得到了M@t-Bu-calix[4]arene和(M@t-Bu-calix[4]arene)Li'(M=Li,Na,K)体系的几何结构. 其中(M@t-Bu-calix[4]arene)Li'(M=Li,Na,K)三个体系各有5个稳定异构体,在前三个异构体中,碱金属与t-Bu-calix[4]arene分子间具有很强的相互作用能,说明了体系的稳定性. 在部分(M@t-Bucalix[4]arene)Li异构体中Li'原子以阴离子形式存在,整个体系表现出碱金属化物的特性. 此外,使用CAMB3LYP方法计算了t-Bu-calix[4]arene及碱金属掺杂后体系的非线性光学性质. 结果表明,t-Bu-calix[4]arene内部掺杂一个碱金属原子M后,体系的一阶超极化率(β0)有较大提高,而在配体外部又掺杂一个Li原子后,体系具有更大的β0值. 其中(M@t-Bu-calix[4]arene)Li'体系的MLi'-4异构体表现出最高的β0值(41827-114354 a.u.),并且随着M原子序数的增加而逐渐增大. 可见,碱金属掺杂是提高t-Bu-calix[4]arene非线性光学响应的一种有效策略.

关键词: 密度泛函理论, 掺杂效应, 碱金属化物, 非线性光学, 一阶超极化率

Abstract:

Using density functional theory with the B3LYP functional, the optimized geometrical structures of the M@t-Bu-calix[4]arene and (M@t-Bu-calix[4]arene)Li' (M=Li, Na, K) compounds were obtained. Five stable isomers were identified for each bi-alkali-metal-doped (M@t-Bu-calix[4]arene)Li' species. The first three lowlying isomers have considerable intramolecular interaction energies between alkali metal atoms and the t-Bucalix[4]arene molecule, indicating their stabilities. According to natural bond orbital analyses, the outside Li' atom is negatively charged in some (M@t-Bu-calix[4]arene)Li' structures, indicating the alkalide characteristics of these isomers. In addition, the nonlinear optical (NLO) properties of isolated and alkali-metal-doped t-Bu-calix [4]arene molecules were calculated using the CAM-B3LYP method. The results indicate that the single-doped effect of alkali metalMgreatly enhances the first hyperpolarizability (β0) of the t-Bu-calix[4]arene molecule. In particular, when another Li atomis doped outside the M@t-Bu-calix[4]arene species, the resulting (M@t-Bucalix[4]arene)Li' compounds exhibit larger β0 values. Obviously, the alkali-metal-doping effect plays a crucial role. The MLi'-4 conformation has the largest β0 value (41827-114354 a.u.) among all the (M@t-Bu-calix[4]arene) Li' structural isomers, and it is found that the β0 value of (M@t-Bu-calix[4]arene)Li' gradually increases with increasing atomic number of the alkali metal M. Therefore, alkali-metal doping is an effective approach to enhance the NLOresponse of the t-Bu-calix[4]arene molecule.

Key words: Density functional theory, Doping effect, Alkalide, Nonlinear optics, First hyperpolarizability

MSC2000: 

  • O641