title: Thermal and magnetic properties and vibrational analysis of 4-(dimethylamino) pyridine: a quantum chemical approach.
abstract: The FT-IR and FT-Raman spectra of 4-(dimethylamino) pyridine (4DMAP) have been recorded in the region 4000-500 cm(-1)and 3500-100 cm(-1). Quantum chemical calculations of energy, geometry and vibrational wavenumbers of 4DMAP were carried out by using ab initio HF and density functional theory (DFT/B3LYP) with complete relaxation in the potential energy surface using 6-311++G(d,p) basis set. The harmonic vibrational wavenumbers were calculated and the scaled wavenumbers have been compared with the experimental FT-IR and FT-Raman spectra. The quantum chemical parameters have been computed from the HOMO-LUMO energy values. Temperature dependence thermodynamic parameters and magnetic properties of the title compound have been analyzed. Using NBO analysis the stability of the molecule arising from hyper-conjugative interactions, charge delocalization has been analyzed. The first-order hyper-polarizability (β) values of the title molecule were computed by B3LYP method. Finally the theoretically spectrograms for FT-IR and FT-Raman spectra of the title molecule have been constructed which show good agreement with recorded spectra.
authors: Centre for Research, Department of Physics, A A. Government Arts College, Musiri 621 211, India. Electronic address: brsbala@rediffmail.com.
authors: V
authors: V
authors: Balachandran
authors: P.G. & Research Department of Physics, Periyar EVR College(Autonomous), Tiruchirappalli 620 023, India.
authors: S
authors: S
authors: Rajeswari
authors: P.G. & Research Department of Physics, Periyar EVR College(Autonomous), Tiruchirappalli 620 023, India.
authors: S
authors: S
authors: Lalitha
mesh_terms: D015761:4-Aminopyridine / Q000031:analogs & derivatives* / Q000737:chemistry; D004583:Electrons; D060328:Magnetic Phenomena; D008958:Models, Molecular; D008968:Molecular Conformation; D011789:Quantum Theory; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D013696:Temperature; D014732:Vibration
chemical_list: D015761:4-Aminopyridine; C003885:4-dimethylaminopyridine
keywords: 4DMAP; FT-IR; FT-Raman; HOMO–LUMO; NBO; Vibrational spectra