Ab initio and density functional theory calculations of the dipole polarizability and the second dipole hyperpolarizability of benzene

Abstract

ABSTRACT:The linear dipole polarizability α and nonlinear second dipole hyperpolarizability γ of benzene were calculated using the ab initio SCF-MO restricted Hartree-Fock (HF) method. The coupled perturbed HF and time-dependent HF (TDHF) methods were used for the evaluation of the static and dynamic properties, respectively. The TDHF approach was applied at different optical frequencies, and the second hyperpolarizability γ was evaluated for different optical processes. Electron correlation was taken into account by using the Møller-Plesset perturbation theory (MP2) and the density functional theory B3LYP hybrid approach, with a finite field method, with electric fields of ±0.01, ±0.02, ±0.03, and ±0.04 a.u. used. Benzene was assumed to have a D 6 h geometry, and the standard STO/6-31+G(d, p) (A) and optimized STO/6-31+G(d * , p) (B) basis sets were employed for the calculations. In the optimized basis set, the d exponent of the C atomic function was varied in order to obtain a maximum static benzene γ at the TDHF level of theory. This optimized basis set was able to gives values for the

Conformational dependence of the second hyperpolarizability of quadrupolar molecules

“…Therefore, the electron correlation effects on the NLO properties for molecules in the Fig. 1 can be well approximated at MP2/6-31+G(d,p) level and a field intensity of 0.01 au, which is in agreement with previous reports [21,33,36].…”

“…The tensor components for hai and hci were calculated with the GAMESS program [35], using the FF method and electric field intensity of E = 0.01 au. This intensity has been shown to be appropriate to give good agreement with the experimental hai and hci values found in many organic molecules [36]. Nevertheless, calculations were performed for two different field intensities and the results compared and analyzed in order to confirm this conclusion.…”

“…In fact, a large number of NLO calculations using AM1 to PM3 methods can be found in the literature [24,25]. Recently a new parameterization, called PM6, has been implemented in the MOPAC2007 package [36]. In this paper, we also have applied the PM3 and PM6 methods and the results are displayed in Tables 1 and 2.…”

“…This latter method has proved to be highly efficient in calculating the polarizabilities of polycyclic aromatic molecules and in studies of complex chemical reactions of biological interest [24,25]. As compared to the previous semiempirical methods AM1 and PM3, in PM6 several modifications have been made to the NDDO approximation to improve the prediction of geometries and corecore interaction for NAO, NAH, OAH and CAC bonds as also to improve the prediction of behavior of the nitrogen sp 2 pyramidalization [36]. These results lead us to check and validate the performance of the PM6 method in the calculation of hai and hci of the quadrupolar molecules shown in Fig.…”

Polarizability and optical rotation calculated from the approximate coupled cluster singles and doubles CC2 linear response theory using Cholesky decompositions

“…Among the correlated calculations, Christiansen, Hättig, and Jørgensen 31 obtained an average polarizability of 69.17 a.u. at the CCSD level with Sadlej's basis set, while Soscún et al 33 reported 67.25 a.u. using DFT/ B3LYP and a modified 6-31ϩG(d, p) basis set.…”