This work deals with the synthesis, computational molecular modeling, and vibrational/electronic spectroscopic analysis of the coordination complex [Fe(DDTC)₂]. The complex was synthesized according to the guidelines provided by the graphical method. The optimization of the molecular structure was performed using Density Functional Theory with the exchange functional B3LYP and basis set 6–311G(d,p). The experimental FT-IR and Raman spectra of the complex were recorded in the range of 4000–0 cm⁻¹ to correlate them with the calculated spectra. Most of the DFT calculated frequencies agreed with the experimental results, and complete vibrational assignments (including metal-ligand) were made. To investigate the internal electronic mobility of the complex, we performed natural bond orbital analysis (NBO), which provided information regarding intramolecular charge transfer interactions resulting from the overlapping of bonding and antibonding orbitals. The NBO analysis also provided information about the electronic distribution between the HOMO and LUMO orbitals due to charge transfers. We found that the NBO analysis provided the main charge transfers between donor and acceptor atoms, and the HOMO-LUMO energy gap revealed that the complex has high kinetic stability. We also correlated the calculated and experimental UV–Vis spectra to investigate the configurations of several excited states of the complex that involve intra-ligand transitions. The charge transfer and d-d (Laporte Forbidden) bands were assigned. The results also corroborate the existence of several Ligand to Metal Charge Transfer (LMCT) and Metal to Ligand Charge Transfer (MLCT) transitions, as well as d-d transitions. We found that the experimental vibrational spectra agreed with the theoretical ones.

这项工作涉及配位络合物 [Fe(DDTC) ₂ ] 的合成、计算分子建模和振动/电子光谱分析。该复合物是根据图形方法提供的指南合成的。使用具有交换功能 B3LYP 和基组 6–311G(d,p) 的密度泛函理论进行分子结构的优化。复合物的实验 FT-IR 和拉曼光谱记录在 4000–0 cm ^-1范围内将它们与计算出的光谱相关联。大多数 DFT 计算的频率与实验结果一致，并进行了完整的振动分配（包括金属配体）。为了研究复合物的内部电子迁移率，我们进行了自然键轨道分析 (NBO)，该分析提供了有关由键合和反键合轨道重叠引起的分子内电荷转移相互作用的信息。NBO 分析还提供了由于电荷转移导致的 HOMO 和 LUMO 轨道之间电子分布的信息。我们发现 NBO 分析提供了供体和受体原子之间的主要电荷转移，HOMO-LUMO 能隙表明该络合物具有高动力学稳定性。我们还将计算的和实验的 UV-Vis 光谱相关联，以研究涉及配体内跃迁的复合物的几种激发态的构型。电荷转移和d -d (Laporte Forbidden) 频段被分配。结果还证实了几种配体到金属电荷转移 (LMCT) 和金属到配体电荷转移 (MLCT) 跃迁以及d -d 跃迁的存在。我们发现实验振动光谱与理论振动光谱一致。