Table of Contents
ISRN Physical Chemistry
Volume 2012, Article ID 262563, 8 pages
Research Article

Theoretical Study of Effect of the Number of N,N-dimethyl-4-nitroaniline Units in Novel “Parallel Connection” Chromophores on Its Nonlinear Optical Properties

1Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science & Engineering, Nanjing University of Information Science & Technology, Nanjing 210044, China
2Department of Theoretical Chemistry, School of Biotechnology, Royal Institute of Technology, 106 91 Stockholm, Sweden

Received 5 August 2011; Accepted 17 September 2011

Academic Editors: T. Kar, H. Reis, and M. Sliwa

Copyright © 2012 Chao-Zhi Zhang et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Design of “parallel connection” chromophores could give a way of acquiring effective chromophores. The semiempirical method ZINDO was employed to study relationship between static first hyperpolarizabilities of “parallel connection” chromophores and the number of parallel nonconjugated N,N-dimethyl-4-nitroaniline (DMNA) units in the chromophore. The results show that the chromophore containing three parallel non-conjugated DMNA units exhibits the highest static first hyperpolarizability, which is 1.8 times that of chromophore DMNA. However, static first hyperpolarizabilities of the chromophores containing four or five DMNA units are very small. The absorption maximum wavelength (𝜆max) of “parallel connection” chromophores is remarkably shorter (34.9 nm–38.1 nm) than that of 1DMNA. Therefore, the “parallel connection” chromophore containing three DMNA units would be an effective chromophore with a large first hyperpolarizability and a good optical transparency. It could give a useful suggestion for designing effective chromophores containing parallel non-conjugated D-π-A units.