Synthesis and Crystal Structure of a Novel Copper Complex Cu(Phen)(C8H7O2) 2
Reactions of a freshly prepared Cu(OH)2×yH2O precipitate, 2-methyl benzoic acid with 1,10’-phenanthroline in C2H5OH/H2O afforded Cu(phen)(C8H7O2)2. The title compound was structurally characterized by X-ray diffraction methods. The unit of complex molecule was proposed 4+2 coordination sphere. In the crystal, molecules are connected by aryl π-π packing forming chains along  direction, the supramolecular double chains are further constructed two-dimension layers which parallel to (011) by π-π packing interactions.
Fei Hu and Beibei Wang
P. Xia "Synthesis and Crystal Structure of a Novel Copper Complex Cu(Phen)(C8H7O2) 2", Advanced Materials Research, Vol. 279, pp. 132-135, 2011