Coordination-driven self-assemblies of two hetero‐trinuclear [Cu(II)₂Ln(III)] (Ln = La and Ce) complexes with a flexible bis(salamo)‐type ligand

Abstract

d-Block transition metal(II)-lanthanide(III) (3d-4f) hetero‐trinuclear [Cu(II)₂Ln(III)] (Ln = La and Ce) complexes [Cu₂La(L)(ƞ²-NO₃)₃(CH₃OH)₂]·2CH₃OH (1) and [Cu₂Ce(L)(ƞ²-NO₃)₃(CH₃OH)₂]·2CH₃OH (2) are described, both of which are formed by a flexible symmetrical bis(salamo)-type ligand H₄L. The two 3d-4f complexes have been synthesized and characterized by elemental analyses, IR spectra and UV–Vis spectroscopy. The crystal structures of 1 and 2 were determined by single-crystal X-ray diffraction analyses. In 1 and 2, each Cu(II) ion (Cu1 or Cu2) is located in the N₂O₂ cavity of an (L)⁴⁻ unit, while the apex is occupied by one oxygen atom of the coordinated methanol molecule, forming a penta-coordinated square pyramidal geometry. The lanthanide(III) (La or Ce) ion is located in the O₆-donor coordination sphere of the completely deprotonated (L)⁴⁻ unit and coordinated with the other six oxygen atoms of the three nitrate ligands to form a twelve-coordinated icosahedron. At the same time, the supramolecular structures are formed by intermolecular hydrogen bonding interactions and quantitatively determined by Hirshfeld surfaces analyses. Fluorescence properties and DFT calculations of 1 and 2 were also studied.

Graphical Abstract

Keywords:

• Flexible bis(salamo)-type ligand
• hetero‐trinuclear complex
• crystal structure
• DFT and Hirshfeld calculation
• fluorescence property

Acknowledgment

This work was supported by the National Natural Science Foundation of China (21761018), which is gratefully acknowledged.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (21761018), which is gratefully acknowledged.