Acta Phys. -Chim. Sin. ›› 2014, Vol. 30 ›› Issue (7): 1223-1229.doi: 10.3866/PKU.WHXB201405091

• THEORETICAL AND COMPUTATIONAL CHEMISTRY • Previous Articles     Next Articles

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).

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