Synthesis, structural analyses and antimicrobial activity of the water soluble 1D coordination polymer [Ag(3-aminopyridine)]ClO4

The synthesis, characterization and molecular structure aspects of the [Ag(3-aminopyridine)]ClO4 coordination polymer have been presented. Single crystal X-ray diffraction (SC-XRD) analysis showed that the asymmetric unit consists of two Ag, one 3-aminopyridine (3APy) and one ionic perchlorate anion. The 3-aminpyridine (3APy) acts as a bridged ligand connecting the Ag-atoms via the amine and pyridine ring N-atoms leading to the formation of 1D coordination polymer. The perchlorate anion connects the 1D chains via a complicated set of N-H center dot center dot center dot O and C-H center dot center dot center dot O hydrogen bonding interactions. Strong FTIR spectral bands at 1143.1, 1116.7 and 1085.6 cm(-1) and a weak band at 932.9 cm(-1) revealed the ionic character of the complex. Single point DFF calculations combined with atoms in molecules (AIM) and natural bond orbital (NBO) analyses indicated stronger Ag-N(py) than Ag-N(NH2) interaction. The former has more covalent character according to the AIM topological parameters. The Ag center dot center dot center dot O interactions are weak and are mainly affected by dispersion interactions. Of the six DFT methods used for geometry optimizations, the TPSSTPSS then PBEPBE are the most powerful DFT methods to predict the Ag-N distances. Effect of methods on the frontier molecular orbitals energies and shapes are also presented. Preliminary antimicrobial studies showed that the [Ag(3APy)]ClO4 complex has more activity against all the studied microorganisms than the free 3APy. (C) 2017 Elsevier B.V. All rights reserved.