title: Molecular structure, NLO, MEP, NBO analysis and spectroscopic characterization of 2,5-dimethylanilinium dihydrogen phosphate with experimental (FT-IR and FT-Raman) techniques and DFT calculations.
abstract: Single crystals of 2,5-dimethylanilinium dihydrogen phosphate were grown by slow evaporation method at room temperature. The synthesized compound was characterized by powder X-ray diffraction analysis to confirm its crystalline nature. The optimized molecular structure, vibrational spectra and the optical properties were calculated by the density functional theory (DFT) method using the B3LYP function with the 6-31G(d,p) basis set. Theoretical simulation of infrared and Raman spectra led to excellent overall agreement with the observed spectral patterns. The complete assignments of the vibrational spectra were carried out with the aid of potential energy distribution (PED). The stability of the molecule arising from hyperconjugative interaction and charge delocalization has been analyzed using natural bond orbital (NBO) analysis leading to high nonlinear optical (NLO) activity. The lowering in the HOMO and LUMO energy gap explains the eventual charge transfer interactions that take place within the molecules.
authors.affiliation: Laboratoire de Physique Appliquée (LPA), Université de Sfax, Faculté des Sciences, BP 1171, 3000 Sfax, Tunisia. Electronic address: sameh_guidara@yahoo.fr.
authors.forename: Sameh
authors.initials: S
authors.lastname: Guidara
authors.affiliation: Laboratoire de Physique Appliquée (LPA), Université de Sfax, Faculté des Sciences, BP 1171, 3000 Sfax, Tunisia.
authors.forename: Habib
authors.initials: H
authors.lastname: Feki
authors.affiliation: Laboratoire de Physique Appliquée (LPA), Université de Sfax, Faculté des Sciences, BP 1171, 3000 Sfax, Tunisia.
authors.forename: Younes
authors.initials: Y
authors.lastname: Abid
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry*; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D008968:Molecular Conformation; D010710:Phosphates / Q000737:chemistry*; D011789:Quantum Theory; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman
chemical_list: D000814:Aniline Compounds; D010710:Phosphates
keywords: 2,5-Dimethylanilinium dihydrogen phosphate; NBO; NLO; Vibrational study