Abstract A novel polymeric complex of Cu(II) ion, [Cu(tfpc)2]n [tfpc: 4-(Trifluoromethyl)pyridine-2-carboxylate] has been prepared and characterized spectroscopically (by FT-IR) and structurally (by single-crystal XRD). The geometry around the Cu(II) center can be described as square planar made by tfpc ligand having nitrogen and oxygen atoms. Additionally, the Cu(II) complex has a one-dimensional double-bridged polymeric structure in which Cu(II) ions are bridged by two oxygen atoms of adjacent planes. The crystal packing has been stabilized by C H⋯O intra and intermolecular hydrogen bonds. The molecular structure of the Cu(II) complex has been optimized using the Density Functional Theory (DFT) B3LYP, B3PW91 and PBEPBE levels with 6-311+G(d,p) basis set. The calculated electronic spectra have been explained using the time dependent DFT (TD-DFT) method by applying the polarized continuum model (PCM). The vibrational spectral data have been calculated and compared with experimental ones. The non-linear optical (NLO) properties of the title compound have been investigated using the DFT method with three different levels. Natural Bond Orbital (NBO) property of the Cu(II) complex has been performed by the B3LYP density functional and the 6-311+G(d,p) basis set.

中文翻译：

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4-(三氟甲基)吡啶-2-羧酸的铜(II)配合物的合成、晶体结构、光谱研究和DFT计算

摘要 制备了一种新型的 Cu(II) 离子聚合物复合物 [Cu(tfpc)2]n [tfpc: 4-(Trifluoromethyl)pyridine-2-carboxylate]，并对其进行了光谱（FT-IR）和结构（通过）表征。单晶XRD）。Cu(II) 中心周围的几何形状可以描述为由具有氮和氧原子的 tfpc 配体制成的方形平面。此外，Cu(II) 配合物具有一维双桥聚合结构，其中 Cu(II) 离子由相邻平面的两个氧原子桥接。CH⋯O分子内和分子间氢键稳定了晶体堆积。使用密度泛函理论 (DFT) B3LYP、B3PW91 和 PBEPBE 水平以及 6-311+G(d,p) 基组优化了 Cu(II) 配合物的分子结构。通过应用偏振连续模型 (PCM)，使用时间相关 DFT (TD-DFT) 方法解释了计算出的电子光谱。计算了振动光谱数据并与实验数据进行了比较。已使用 DFT 方法在三个不同水平上研究了标题化合物的非线性光学 (NLO) 特性。Cu(II) 配合物的自然键轨道 (NBO) 特性已由 B3LYP 密度泛函和 6-311+G(d,p) 基组执行。