Abstract Two new salicylideneaniline (SA) derivative compounds ( E )-2-(((4-chlorophenyl)imino)methyl)-5-(diethylamino)phenol, compound (I), and ( E )-2-(((3-chlorophenyl)imino)methyl)-5-(diethylamino)phenol, compound (II), have been synthesized and characterized by single crystal X-ray diffraction, IR spectroscopy, 1 H NMR, 13 C NMR and theoretical methods. Both of the compounds which are Schiff base derivatives are isomer of each other. While the compound (I) crystallizes in centrosymmetric monoclinic space group P 2 1 /c, the compound (II) crystallizes in orthorhombic space group P 2 1 2 1 2 1 . The theoretical parameters of the molecules have been calculated by using Hartree-Fock (HF) and density functional theory (DFT/B3LYP) with 6-31G (d,p) basis set. These theoretical parameters have been compared with the experimental parameters obtained by XRD. The experimental geometries of the compounds have been superimposed with the theoretical geometries calculated by HF and DFT methods. Furthermore, the theoretical IR calculations, molecular electrostatic potential maps (MEP) and frontier molecular orbitals have been created for the compounds.

中文翻译：

---

(E)-2-(((4-氯苯基)亚氨基)甲基)-5-(二乙氨基)苯酚和(E)-2-(((3-氯苯基)亚氨基)甲基)的晶体学、光谱学和理论研究-5-(二乙氨基)苯酚分子

摘要 两种新的水杨基苯胺 (SA) 衍生化合物 ( E )-2-((((4-氯苯基) 亚氨基) 甲基)-5-(二乙氨基) 苯酚，化合物 (I) 和 ( E )-2-(((3 -氯苯基）亚氨基）甲基）-5-（二乙氨基）苯酚，化合物（II），已经合成并通过单晶X射线衍射、红外光谱、 1 H NMR、 13 C NMR和理论方法表征。作为席夫碱衍生物的两种化合物互为异构体。当化合物(I)在中心对称单斜空间群P 2 1 /c 中结晶时，化合物(II)在正交空间群P 2 1 2 1 2 1 中结晶。分子的理论参数已通过使用 Hartree-Fock (HF) 和密度泛函理论 (DFT/B3LYP) 以 6-31G (d,p) 基组计算。将这些理论参数与通过 XRD 获得的实验参数进行了比较。化合物的实验几何形状与通过 HF 和 DFT 方法计算的理论几何形状叠加。此外，还为这些化合物创建了理论红外计算、分子静电势图 (MEP) 和前沿分子轨道。