Quantum-Chemical, IR, NMR, and X-ray Diffraction Studies on 2-(4-Chlorophenyl)-1-methyl-1H-benzo[d]imidazole

The title molecule, 2-(4-chlorophenyl)-1-methyl-1H-benzo[d]imidazole (C14H11ClN2), was prepared and characterized by H-1 NMR, C-13 NMR, IR, and single-crystal X-ray diffraction. The molecular geometry, vibrational frequencies, and gauge including atomic orbital (GIAO) H-1 and C-13 NMR chemical shift values of the title compound in the ground state have been calculated by using the Hartree-Fock (HF) and density functional theory (DFT/B3LYP) method with 6-31G(d) basis sets, and compared with the experimental data. The calculated results show that the optimized geometries can well reproduce the crystal structural parameters, and the theoretical vibrational frequencies and GIAO H-1 and C-13 NMR chemical shifts show good agreement with experimental values. The energetic behavior of the title compound in solvent media has been examined using B3LYP method with the 6-31G(d) basis set by applying the Onsager and the polarizable continuum model (PCM). Besides, molecular electrostatic potential (MEP), frontier molecular orbitals (FMO) analysis, and nonlinear optical (NLO) properties of the title compound were investigated by theoretical calculations. (C) 2010 Wiley Periodicals, Inc. Int J Quantum Chem 111: 3112-3124, 2011