Dispersion of Linear, Nonlinear Optical Susceptibilities and Hyperpolarizability of C11H8N2O (o-Methoxydicyanovinylbenzene) Crystals

作者：Reshak Ali H^*; Kamarudin H; Kityk I V; Auluck S

来源：Journal of Physical Chemistry B, 2012, 116(45): 13338-13343.

DOI：10.1021/jp3074128

Linear and nonlinear optical susceptibility dispersion and hyperpolarizability of C11H8N2O, o-methoxydicyanovinylbenzene, Crystals were performed by Means of density functional theory (DFT). The exchange and correlation potential was described within a framework of the local density approximation (CA-LDA) and :gradient approximation (GGA) based on exchange-correlation energy optimization to calculate the total energy. Engel-Vosko generalized gradient approximation (EV-GGA) and the modified Becke-Johnson potential (mBJ) were used for the electronic crystal structure and optical susceptibility dispersion calculations. We have established systematically increasing energy gap from 2.25 eV (LDA) 234 eV (GGA) 2.50 eV. (EVGGA) and 2.96 eV (mBJ). The crystal possesses a direct band gap which is an important. key factor to make the crystal optically active with high linear and nonlinear. optical Susceptibilities and,hyperpolarizability. Additionally, the studied crystal has a considerable anisotropy Of birefringence which is necessary for phase matching conditions during the optical second harmonic experiments. We have found that the theoretically evaluated second harmonic generation achieves about 5.8 x 10(-8) esu in good agreement with the experimental value (4.9 x 10(-8) esu). Additionally, we have found that our calculated value of beta(222) is about 2.3 x 10(-30) esu at zero energy and 6.6 x 10(-30) esu at lambda = 1.064 mu m. We should emphasize that our calculated value of beta(222) (6.60 x 10(-30) esu at lambda = 1.064 mu m) shows better agreement with the experimental data (5.04 x 10(-30) esu at lambda = 1.064 mu m) than other calculations.

• 出版日期2012-11-15