In Quest of New Energy Material: 3D Mn (II)-Coordination Polymer, the Schottky Device and Theoretical Interpretation
Abstract
Single crystal X-ray structure of amino-isophthalato bridged Mn (II) co-ordination polymer, {[Mn(asp)(H2O)].(H2O)2}n (1) [H2asp = 5-aminoisophthalic acid] is determined to support previously characterized structure of the polymer. The Tauc’s plot obtained from UV-Visible spectra has determined the optical band gap, 2.53 eV, which corroborates the semiconducting nature. Mn(II) centre is coordinated by four carboxylate-O (one chelated carboxylate-O,O and two monodentate carboxylate-O), one H2O and one -NH2 (of asp2-) to constitute MnO5N distorted octahedral geometry. Bridging carboxylates constitute a 2D coordination polymer and has been assembled through strong noncovalent interactions to form 3D supramolecular aggregate. The determination of various weak interactions in the compound is also supported by Hirshfeld surface analysis. The 3D assembly of 1 shows electrical conductivity in the semiconducting region (barrier height, 0.59 eV) and follows a non-ohmic relation (I α V2), and the conductivity is 4.02 × 10–4 Sm–1 which constitutes Schottky Diode Barrier.