A Cu based layered multifunctional material: (C₈H₁₂N)₂CuCl₄ Optical and electronic properties

Toward the processing of a multifunctional material, single crystals of PEA-CuCl₄ [PEA = (C₆H₅-C₂H₄-NH₃)₂] were obtained by slow evaporation technique. X-ray Diffraction powder, Scanning electron microscopy (SEM) and UV-Visible spectroscopy were used to characterize the purity, the morphology of the compound and the optical properties, respectively. PEA-CuCl₄ crystallizes in Orthorhombic system, C2cb (n^o 64) with a = 39.021(8) Å, b = 7.343 0(15) Å, c = 7.393 9(15) Å and Z = 8. The 3D and 2D Hirshfeld Surfaces analysis reveals the importance of hydrogen bonding in the stability of the bulk. The optical study shows that the compound undergoes an indirect optical transition with phonon assisted Cu²⁺ d-d transitions in the visible region, and presents an energy band gap of about Eg = 2.3 eV. In parallel, the electronic band structures, the electronic densities of states and the energy gap value (Eg = 1.99 eV) were calculated using DFT+U calculations. The calculated and experimental results are in good agreement.