Molecular structure, vibrational spectra, NBO analysis and molecular packing prediction of 3-nitroacetanilide by ab
Xiao-Hong Li1, Tong-Wei Li, Wei-Wei Ju
1College of Physics and Engineering, Henan University of Science and Technology, Luoyang 471023, China; Luoyang Key Laboratory of Photoelectric Functional Materials, Henan University of Science and Technology, Luoyang 471003, China; Department of Chemistry, Nanjing University of Science and Technology, Nanjing 210094, China.
Abstract:
Quantum chemical calculations of geometries and vibrational wavenumbers of 3-nitroacetanilide (C8H8N2O3) in the ground state were carried out by using ab initio HF and density functional theory (DFT/B3LYP) methods with 6-31+G(*) basis set. The -311++G(**) basis set is also used for B3LYP level. The scaled harmonic vibrational frequencies have been compared with experimental FT-IR spectra. Theoretical vibrational spectra of the title compound were interpreted by means of potential energies distributions (PEDs) using MOLVIB program. The theoretical spectrograms for IR spectra of the title compound have been constructed. The shortening of C-H bond length and the elongation of N-H bond length suggest the existence of weak C-H⋯O and N-H⋯O hydrogen bonds, which is confirmed by the natural bond orbital analysis. In addition, the crystal structure obtained by molecular mechanics belongs to the P2(1) space group, with lattice parameters Z=4, a=14.9989 Å, b=4.0367 Å, c=12.9913 Å, ρ=0.998 g cm(-3).
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