Prospective light-harvesting material of L-phenylalaninium selenate monohydrate: Synthesis, thermal behavior, vibrational and optical properties

The present work focuses on the study of a new organo-selenate hybrid material, namely [C9H12NO2](2)SeO4.H2O, abbreviated as (LPA)(2).SeO4.H2O, which was successfully obtained at room temperature by slow evaporation. The structure was studied by the X-ray single-crystal diffraction process. This compound crystallizes in the monoclinic system, with a non-centrosymmetric P2(1) space group and the following lattice parameters: a = 12.817(3) & Aring;; b = 6.272(15) & Aring;; c = 13.629(3) & Aring;, beta=103.847(7)degrees, Z = 2 and V = 1063.7(4) & Aring;(3). The atomic arrangement in the structure is described as an alternation of organic and inorganic entities along the a-axis. The IR and Raman spectra were recorded in the 500-4000 cm(-1) and 10-4000 cm(-1) frequency region, respectively, confirming the existence of vibrational modes that correlate with organic and inorganic groups. The crystal arrangement is determined by hydrogen bonds of the type NH & mldr;O, OH & mldr;O and OW-H & mldr;O. The intermolecular interactions in the crystal structure were quantified and analyzed using Hirshfeld surface analysis. TGA-DTG and DSC analyses have shown that compound dehydration at around 90 degrees C produces an anhydrous compound that is thermically stable until 122 degrees C. Experimental UV-Visible absorption of the compound demonstrated its semiconducting properties, revealing a direct optical band gap at 5.53 eV. Finally, photoluminescence measurements indicate that the synthesized material exhibits solid-state luminescence properties. Optimized geometry and HOMO-LUMO were calculated using the B3LYP/6-311+ G(dd,p) basis set. The theoretical calculations performed by density functional theory are in agreement with the experimental results obtained.