Syntheses and structures of d9 and d10 metal complexes with 2,3,5-pyridinetricarboxylic acid

Three complexes with different structures were obtained by reacting 2,3,5-pyridinetricarboxylic acid (H3pta) with d9 (Cu2+) and d10 (Zn2+, Ag+) ions in water at room temperature. The complexes of [Cu(H2pta)2(H2O)2]·2H2O (1) and [Zn2(Hpta)2(H2O)6]·4H2O (2) are mononuclear and binuclear structures, respectively; while [Ag(H2pta)(H2O)]n (3) is a helical 1D chain coordination polymer. A double chain was further formed in 3 by the weak interaction between oxygen atoms and Ag(I) ions. Through hydrogen bonds the three complexes constructed corresponding 3D network structures. The three complexes were characterized by elemental analyses, IR and single-crystal X-ray diffraction analyses. In addition, TGA, XRD and fluorescence spectra determinations were performed for compounds 2 and 3.