Synthesis, structure, photoluminescence and magnetism of a series of cobalt‐lanthanide heterometallic complexes originated from 2,3‐dichlorobenzoate and 1,10‐phenanthroline

Abstract A series of 3d–4f heterometallic complexes, namely [Ln 2 Co 2 (2,3‐DCB) 10 (phen) 2 ] [Ln=Nd ( 1 ), Sm ( 2 ), Eu ( 3 ), Gd ( 4 ), Tb ( 5 ), Dy ( 6 ), Er ( 7 )], were obtained through the self‐assembly reactions of Ln(NO 3 ) 3 ⋅ n H 2 O, Co(NO 3 ) 2 ⋅ 6H 2 O, 2,3‐dichlorobenzoic acid (2,3‐HDCB), NaOH and 1,10‐phenanthroline (phen) under solvothermal conditions. Their crystal structures were determined by single‐crystal X‐ray diffraction. They were also characterized by elemental analysis, FT‐IR, powder X‐ray diffraction (PXRD) and thermogravimetric analysis (TGA) and differential thermoanalysis (DTA). These seven complexes have the same molecular formula but different crystal structures. Complexes 1 – 3 , 4 and 5 as well as 6 and 7 are crystallographically isomorphous, respectively. They all exhibit zero‐dimensional (0D) linear tetranuclear cluster structures. These 0D linear tetranuclear clusters can be further connected into a two‐dimensional (2D) supramolecular network via the extensive intermolecular π–π interactions between 2,3‐DCB and phen. The photoluminescent properties of 3 , 5 and 6 and the magnetic properties of 1 – 2 and 4 – 7 were investigated. Complex 6 shows a slow magnetic relaxation behavior.