Double-bowed nanoscale decanuclear copper(II) assemblies based on tartaric acid

The tartaric acid (H4L), serving as versatile tectons, link CuII atoms with three different bridging modes to form a unique double-bowed nanosized Cu10-assembly, namely, [CuII10(H2L)4(HL)4]·(apy)8·13H2O (1) (apy = 2-aminopyridine). Single-crystal analysis reveals that the nano-cluster is composed of two bow-shaped pentameric subunits joined together by carboxyl O bridges, in which eight CuII atoms are in distorted octahedral site, while the other two CuII atoms display the square-pyramidal geometries. Interestingly, such decanuclear SUBs are connected by R 2 2 (12) H-bonding rings into a 3D α-Po network. Magnetic studies show an antiferromagnetic interaction between CuII centers.