“…In an effort to explore new copper(II) complexes with novel magnetic properties, we selected the picolinic acid N-oxide (HL) as a bridging ligand. Although a number of transition metal complexes with picolinic acid N-oxide have been reported [8][9][10][11][12][13][14], to the best of our knowledge, only one mononuclear copper(II) complex, [Cu(L) 2 (H 2 O) 2 ], has been reported [15]. Reaction of CuCl 2 with HL in acetone/THF mixed solvent afforded a new copper complex, [Cu(L)Cl(H 2 O)] 2 , whose structure features a layer built from Cu 2 O 2 dimeric units.…”