title: Investigation of structure, vibrational, electronic, NBO and NMR analyses of 2-chloro-4-nitropyridine (CNP), 2-chloro-4-methyl-5-nitropyridine (CMNP) and 3-amino-2-chloro-4-methylpyridine (ACMP) by experimental and theoretical approach.
abstract: This study reports about the optimized molecular structures, vibrational wavenumbers, atomic charges, molecular electrostatic potentials, NBO, electronic properties, (1)H NMR and (13)C NMR chemical shifts for the molecules 2-chloro-4-nitropyridine (CNP), 2-chloro-4-methyl-5-nitropyridine (CMNP) and 3-amino-2-chloro-4-methylpyridine (ACMP). Theoretical calculations were performed by density functional theory (DFT)/B3LYP method using 6-311++G (d,p) basis set. The stability and charge delocalization of the title molecules were studied by natural bond orbital (NBO) analysis. Molecular electrostatic potential maps (MEP) were calculated to predict the reactive sites. The reactivity of the title compounds were investigated by HOMO-LUMO energies and global descriptors. The electronic properties of the compounds were also discussed and the transitions were found to be π→π(∗). In addition, the thermodynamic properties were studied for the title compounds and corresponding relations between the properties and temperature were also discussed. The hyperpolarizability values (βtot) were calculated for the title compounds. Hyperpolarizability value (βtot) of CMNP was found to be high and nineteen times greater than that of urea.
authors.affiliation: Department of Physics, Periyar University, Salem 636011, Tamil Nadu, India. Electronic address: gvelraj@yahoo.co.uk.
authors.forename: G
authors.initials: G
authors.lastname: Velraj
authors.affiliation: Department of Physics, Selvamm Arts and Science College (Autonomous), Namakkal 637003, Tamil Nadu, India.
authors.forename: S
authors.initials: S
authors.lastname: Soundharam
authors.affiliation: Department of Physics, Sona College of Technology, Salem 636005, Tamil Nadu, India.
authors.forename: C
authors.initials: C
authors.lastname: Sridevi
mesh_terms: D000465:Algorithms; D002626:Chemistry, Pharmaceutical; D004583:Electrons; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D015394:Molecular Structure; D016011:Normal Distribution; D011725:Pyridines / Q000737:chemistry*; D012984:Software; D013053:Spectrophotometry; D055672:Static Electricity; D014508:Urea / Q000737:chemistry
chemical_list: C000600892:2-chloro-4-methyl-5-nitropyridine; C000600891:2-chloro-4-nitropyridine; C000600893:3-amino-2-chloro-4-methylpyridine; D011725:Pyridines; C052728:4-nitropyridine; D014508:Urea
keywords: 2-Chloro-4-methyl-5-nitropyridine; 2-Chloro-4-nitropyridine; 3-Amino-2-chloro-4-methylpyridine; DFT; NMR