Tanak Hasan, Ağar Ayşen Alaman, Büyükgüngör Orhan
Department of Physics, Faculty of Arts and Sciences, Amasya University, 05100 Amasya, Turkey.
Spectrochim Acta A Mol Biomol Spectrosc. 2014 Jan 24;118:672-82. doi: 10.1016/j.saa.2013.08.054. Epub 2013 Aug 28.
The Schiff base compound (E)-N'-((5-nitrothiophen-2-yl)methylene)-2-phenoxyaniline has been synthesized and characterized by IR, UV-Vis, and X-ray diffraction (XRD) methods. The molecular geometry from X-ray experiment in the ground state has been compared using the density functional theory (DFT) with the 6-311++G(d,p) basis set. The calculated results show that the optimized geometry can well reproduce the crystal structure, and the theoretical vibrational frequency values show good agreement with experimental values. By using TD-DFT method, electronic absorption spectra of the title compound have been predicted and a good agreement with the TD-DFT method and the experimental one is determined. The energetic behavior of the title compound in solvent media has been examined using B3LYP method with the 6-311++G(d,p) basis set by applying the Onsager and the integral equation formalism polarizable continuum model (IEF-PCM). The predicted nonlinear optical properties of the title compound are greater than ones of urea. In addition, DFT calculations of the title compound, molecular electrostatic potential (MEP), natural bond orbital (NBO) and thermodynamic properties were performed at B3LYP/6-311++G(d,p) level of theory.
席夫碱化合物（E）-N'-（（5-硝基噻吩-2-基）亚甲基）-2-苯氧基苯胺已通过红外光谱（IR）、紫外可见光谱（UV-Vis）和X射线衍射（XRD）方法进行了合成与表征。利用密度泛函理论（DFT）和6-311++G（d，p）基组，对基态下X射线实验得到的分子几何结构进行了比较。计算结果表明，优化后的几何结构能够很好地再现晶体结构，理论振动频率值与实验值吻合良好。采用TD-DFT方法预测了标题化合物的电子吸收光谱，并确定了其与TD-DFT方法和实验结果的良好一致性。利用B3LYP方法和6-311++G（d，p）基组，通过应用Onsager和积分方程形式极化连续介质模型（IEF-PCM），研究了标题化合物在溶剂介质中的能量行为。预测的标题化合物的非线性光学性质大于尿素的非线性光学性质。此外，在B3LYP/6-311++G（d，p）理论水平上对标题化合物进行了分子静电势（MEP）、自然键轨道（NBO）和热力学性质的DFT计算。
