Synthesis, crystal structure, and magnetic properties of a new tetranuclear Cu(II) Schiff base compound

Abstract

A new tetranuclear Cu(II) compound [Cu 4(HL) 2(L) 2(ClO 4) 2] ( 1) was synthesized from the reaction of Cu(ClO 4) 2 · 6H 2O with Schiff base ligand (H 2L) condensed from ethanolamine with 2-hydroxyacetophenone. X-ray diffraction studies revealed that 1 is formed from the self-assembly of two dinuclear units [Cu 2(HL)(L)(ClO 4)] through the doubly phenoxo bridging. The variable temperature magnetic susceptibility measurements were performed between 300 K and 2 K and show χ M T value for 1 at 300 K is 1.395 cm 3 mol −1 K and fall to 0.0459 cm 3 mol −1 K at 2 K. These values are smaller than that expected for tetranuclear copper (II) units, indicating antiferromagnetic coupling present in the compound. This result is also confirmed from the DFT calculations.