X-ray and infrared spectrum on metal complexes with indolecarboxylic acids: Part V. Catena-poly[{aqua(η2-indole-3-propionato-O,O′)zinc}-η2-:-μ-indole-3-propionato-O,O′:-O]

The catena-poly{aqua(η²-indole-3-propionato-O,O′)zinc}-η²-:-μ-indole-3-propionato-O,O′:-O], Zn(I3PA)₂(H₂O)]_n was prepared and characterized by infrared spectroscopy and X-ray structure determination. The crystals are monoclinic, space group Pc, with a = 21.380(2), b = 5.9076(7), c = 8.1215(9) Å, V = 1020.2(2) Å³ and Z = 2. The central zinc atom shows the coordination distorted from ideal octahedral. Each zinc centre is coordinated by two oxygen atoms of the bidentate chelating indole-3-propionato (I3PA), two oxygen atoms tridentate chelating-bridging I3PA, water molecule and one oxygen atom tridentate chelating-bridging I3PA from an adjacent Zn(I3PA)₂(H₂O)] unit. The infrared spectrum of Zn(I3PA)₂(H₂O)]_n in the solid state is supported by X-ray analysis. The theoretical wavenumbers and infrared intensities have been calculated by the density functional methods (B3LYP and mPW1PW) with the 6-311++G(d,p)/LanL2DZ basis sets. The theoretical wavenumbers, infrared intensities show a good agreement with experimental data. Detailed band assignment has been made on the basis of the calculated potential energy distribution (PED).