Combined experimental and theoretical study on structural, spectroscopic and electronic properties of the Cu(II) complex of 4′-(2,4-dimethoxyphenyl)-2,2′:6′,2″-terpyridine
Journal of the Indian Chemical Society, cilt.103, sa.8, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 103 Sayı: 8
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.jics.2026.102773
- Dergi Adı: Journal of the Indian Chemical Society
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, EMBASE
- Anahtar Kelimeler: Crystal structure, Cu(II) complex, Electronic properties, Spectroscopic analysis, Terpyridine derivative
- Ondokuz Mayıs Üniversitesi Adresli: Evet
Özet
In this study, a Cu(II) complex containing the ligand 4′-(2,4-dimethoxyphenyl)-2,2′:6′,2″-terpyridine was synthesized, and its structural, spectroscopic, and electronic properties were investigated using combined experimental and theoretical approaches. Single-crystal X-ray diffraction analysis revealed that the Cu(II) center adopts a five-coordinate distorted square pyramidal geometry coordinated by three nitrogen atoms of the terpyridine ligand and two nitrogen atoms of two terminal azide ligands. The experimental geometric parameters showed good agreement with density functional theory (DFT) calculations performed using the HSEH1PBE functional. FT-IR vibrational bands were supported by scaled DFT frequency calculations, confirming the proposed coordination environment. Frontier molecular orbital analysis revealed a moderately reactive electronic structure with a HOMO–LUMO energy gap of approximately 2.0 eV, indicating pronounced charge-transfer character. Time-dependent DFT calculations successfully reproduced the main experimental UV–Vis absorption features and clarified the nature of the electronic transitions. Complementary electronic structure analyses further demonstrated partially delocalized metal–ligand interactions and a polarized electronic distribution associated with significant charge transfer along the metal–ligand axis. In addition, intermolecular interaction analyses revealed that weak dispersive and hydrogen-related interactions contribute significantly to the stabilization of the crystal packing. Overall, the results indicate that the synthesized Cu(II) complex possesses a polarized and partially delocalized electronic structure strongly influenced by metal–ligand charge-transfer interactions.