Newly designed and synthesized heterobimetallic [Cu^II–Dy^III] salamo-like complex: structural characterization, DFT calculation, and fluorescent property

Abstract

A heterobimetallic 3d–4f complex [Cu(L)Dy(NO₃)₃] based on a symmetric salamo-like ligand (H₂L) was synthesized and characterized by elemental analyses, IR, UV-Vis spectroscopy, and single-crystal X-ray diffraction. The complex crystallized in the monoclinic, space group P 2₁/c, included one tetra-coordinated Cu(II) atom (Cu1), one deca-coordinated Dy(III) atom (Dy1), one completely deprotonated (L)²⁻ unit, and three nitrate groups involved in coordination. Cu1 adopted a planar quadrilateral configuration, and Dy1 formed a slightly distorted double-cap square antiprism geometry. The complex finally formed an infinite 2D and 3D supramolecular structure via the intermolecular hydrogen bonds and π–π interactions. Due to the paramagnetism of Cu²⁺ ions, the complex showed fluorescence quenching. The electronic structure and stability of the complex were proved by density functional theory (DFT) calculation.

Keywords:

• Salamo-like ligand
• heterobimetallic 3d–4f complex
• structure
• fluorescence property
• DFT

Additional information

Funding

This research was funded by the National Natural Science Foundation of China (Grant No. 21761018), the Science and Technology Program of Gansu Province (Grant No. 18YF1GA057), and the Program for Excellent Team of Scientific Research in Lanzhou Jiaotong University (Grant No. 201706)