Bis(p-aminobenzoato)bis(hexadecanoato)dicopper(II): A low-temperature and thermally-stable functional metallomesogen


  • Ahmad Nazeer Che Mat
  • Mohamad Isa Mohamadin



Copper(II) mixed-carboxylates, one-pot synthesis, electronic structure, structure elucidation, liquid crystals


A novel copper (II) mixed carboxylates namely bis(p-aminobenzoato)bis(hexadecanoato)dicopper(II), [Cu2(p-H2NC6H4COO)2(CH3(CH2)14COO)2],  from one-pot self-assembly of the corresponding ions was designed to function as a low-temperature and thermally-stable metallomesogen applications. The as-prepared copper (II) complex was characterized by means of CHNS analysis, Fourier Transform Infrared (FTIR) spectroscopy, Ultraviolet-Visible (UV-Vis) spectroscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), optical polarized microscopy (OPM), magnetic Gouy balance, and cyclic voltammetry (CV) for the determination of its elemental compositions, chemical boding, optical properties, thermal stability, phase transition, magnetic properties and electrochemical behavior of the complex, respectively. Its melting and decomposition temperatures are 115 oC and 256 oC, respectively, and formed a smectic C mesophase on cooling from the isotropic liquid phase. Its room-temperature effective magnetic moment is 2.89 B.M., indicating a paramagnetic complex with negligible electronic communication between the two Cu(II) centers. Cyclic voltammetry shows two sets of overlapping peaks at -0.33 V and -0.38 V corresponding to Cu(II)Cu(II)-Cu(II)Cu(I) and Cu(II)Cu(I)-Cu(I)Cu(I) indicating diffusion-controlled, quasireversible reaction accompanied by extensive structural reorganizations.


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