Synthesis, crystal growth, structural characterization and theoretical investigations of bis(benzene-1,2-dicarboxylato)bis(thiourea)zinc

GRAPHICAL ABSTRACT

ABSTRACT

Single crystals of bis(benzene-1,2-dicarboxylato)bis(thiourea)zinc (ZTP) were successfully grown by slow evaporation solution growth technique and characterized by means of single-crystal X-ray diffraction analysis. The compound C₁₈H₁₈N₄O₈S₂Zn crystallizes at monoclinic system with centrosymmetric space group C2/c and its structure is built up from tetrahedral (ZnO₂S₂) linked to each other through the phthalate and thiourea groups. The good crystallinity of the as-synthesized specimen is confirmed by the powder X-ray diffraction pattern. The band gap energy is estimated using diffuse reflectance data by the application of Kubelka – Munk algorithm. Photoluminescence exhibits fluorescent emission of ZTP in the solid state at room temperature. The scanning electron microscopy (SEM) images reveal the surface morphology and the presence of Zn(II) in the specimen is further confirmed by the energy dispersive X-ray spectroscopy. Theoretical calculations were performed using density functional theory (DFT) method to derive the optimized geometry, dipole moment and polarizability.

KEYWORDS:

• Band gap
• crystal
• fluorescent emission
• X-ray diffraction

Funding

One of the authors C. Balakrishnan thank the Science and Engineering Research Board (SERB), New Delhi, for financial support through research project (File No. EMR/2014/000618).

Supplementary information

CCDC1537502 contains the supplementary crystallographic data for this article. These data can be obtained free of charge from The Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/datarequest/cif.