Department of Physics, Celal Bayar University, Manisa, Turkey.
Spectrochim Acta A Mol Biomol Spectrosc. 2013 Oct;114:38-45. doi: 10.1016/j.saa.2013.05.049. Epub 2013 May 23.
In this study; the experimental (NMR, infrared and Raman) and theoretical (HF and DFT) analysis of dinicotinic acid were presented. (1)H and (13)C NMR spectra were recorded in DMSO solution and chemical shifts were calculated by using the gauge-invariant atomic orbital (GIAO) method. The vibrational spectra of dinicotinic acid were recorded by FT-Raman and FT-IR spectra in the range of 4000-10 cm(-1) and 4000-400 cm(-1), respectively. To determine the most stable neutral conformer of molecule, the selected torsion angle was changed every 10° and molecular energy profile was calculated from 0° to 360°. The geometrical parameters and energies were obtained for all conformers form from density functional theory (DFT/B3LYP) and HF with 6-311++G(d,p) basis set calculations. However, the results of the most stable neutral and two anion forms (anion(-1) and anion(-2) forms) of dinicotinic acid are reported here. The complete assignments were performed on the basis of the total energy distribution (TED) of the vibrational wavenumbers, calculated with scaled quantum mechanics (SQM) method and PQS program.
在这项研究中，介绍了二烟酸的实验（NMR、红外和拉曼）和理论（HF 和 DFT）分析。在 DMSO 溶液中记录了（1）H 和（13）C NMR 谱，并使用规范不变原子轨道（GIAO）方法计算了化学位移。二烟酸的振动光谱通过 FT-Raman 和 FT-IR 光谱在 4000-10 cm(-1)和 4000-400 cm(-1)范围内记录。为了确定分子的最稳定中性构象，选择的扭转角每隔 10°改变一次，并从 0°到 360°计算分子能量曲线。从密度泛函理论（DFT/B3LYP）和 HF 与 6-311++G(d,p)基组计算中获得了所有构象的几何参数和能量。然而，这里只报告了二烟酸的最稳定中性和两种阴离子形式（阴离子(-1)和阴离子(-2)形式）的结果。完全分配是基于振动波数的总能量分布（TED）进行的，使用量子力学（SQM）方法和 PQS 程序进行了计算。
