Structural, DFT, optical dispersion characteristics of novel [DPPA-Zn-MR(Cl)(H2O)] nanostructured thin films

Abstract

The spin coating technique has been utilized to deposit good adhesion successfully and highly uniform [DPP-Zn(Cl)2(H2O)2], [DPPA-Zn(Cl)2(H2O)2] and [DPPA-Zn-MR(Cl)(H2O)] thin films. The fabricated film thicknesses ranged from 100 to 150 nm. The molecular structure characteristics of compounds have been investigated by FT-IR, 1H NMR, and FAB-Mass spectroscopic. The structural and morphological properties of [DPP-Zn(Cl)2(H2O)2], [DPPA-Zn(Cl)2(H2O)2] and [DPPA-Zn-MR(Cl)(H2O)] thin films were examined by X-ray diffraction (XRD), and scanning electron microscope (SEM), respectively. According to the density functional calculations (DFT) results, the interaction of the zinc complexes conforms to lose associations, the interaction energies for all complexes in the matrix. The bonding mechanism of the zinc complexes includes both σ-dative and π-back bonding components. The measured optical properties of [DPP-Zn(Cl)2(H2O)2], [DPPA-Zn(Cl)2(H2O)2] and [DPPA-Zn-MR(Cl)(H2O)] thin films such as transmittance (T), absorbance (A) and reflectance (R) in UV-vis-NIR spectrum has been used to calculate optical features at room temperatures. The electrophilicity index (ω) of this zinc complexes are ≅ 10.86–13.84. These are significant interesting quantum chemical characteristics. The transparency of the complexes is within the range of ≅ 85–90% in the visible range. The optical band gap (Ego) of [DPP-Zn(Cl)2(H2O)2], [DPPA-Zn(Cl)2(H2O)2] and [DPPA-Zn-MR(Cl)(H2O)] thin films were estimated by DFT and they found to be 1.045, 0937 and 0.736 eV, respectively. The refractive index (n) and the single oscillator energy (Eo) were discussed by the single oscillator Wemple–Didomenico (WD) model. The high accuracy of the novel zinc complexes along with its appropriate optical band gap enabled us to build an efficient visible-blind UV-photodetector, indicating its potential in optoelectronic applications.