Theoretical and experimental investigation of structural, thermal, and vibrational properties of Bis-glycine hydrochlorobromide crystal

• Published in: Journal of materials science. Materials in electronics 2023-03, Vol.34 (7), p.671, Article 671
• Main Authors: de Oliveira Lopes, Jardel Bruno, de Oliveira Neto, João Gomes, Junior, José Joatan Rodrigues, da Silva Filho, José Gadelha, de Freitas Façanha Filho, Pedro, dos Santos, Adenilson Oliveira
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemical composition; Chemistry and Materials Science; Crystal growth; Density functional theory; Glycine; KDP crystals; Materials Science; Melting points; Nonlinear optics; Optical and Electronic Materials; Optical properties; Optoelectronic devices; Potassium phosphates; Raman spectra; Raman spectroscopy; Rietveld method; Second harmonic generation; Single crystals; Spectrum analysis; Thermal analysis; Unit cell; X ray fluorescence analysis; X-ray diffraction
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-023-10070-0

The synthesis and characterization of crystals with nonlinear optical (NLO) properties have increased considerably due to their potential applications for optoelectronic devices. Bis-glycine hydrochlorobromide monocrystals (BGHClBr) were grown by the slow solvent evaporation method. The obtained samples were characterized by X-Ray Fluorescence (XRF), X-ray diffraction (XRD), Raman spectroscopy, and differential scanning calorimetry (DSC). The XRF technique has confirmed the presence of chloride and bromide ions in the chemical composition of the crystal. The XRD data and further analysis by Rietveld method show that BGHClBr crystal is a crystalline solid isomorphic of Bis-glycine hydrochloride (BGHCl) and Bis-glycine hydrobromide (BGHBr) crystals. The BGHClBr crystal is an orthorhombic structure with parameters a  = 5.369(1) Å, b  = 8.187(1) Å, and c  = 18.276(6) Å belongs to the spatial group (P2 1 2 1 2 1 ) and has two asymmetric units per unit cell. The crystal unit cell of the title compound was simulated by Density-functional theory (DFT) method, and the geometrical results were compared with the XRD data. Those results allow a complete assignment of vibrational normal modes observed in the experimental FT-IR and Raman spectra. The thermal analysis indicates that BGHClBr is stable up to the melting point at 444 K. The Second Harmonic Generation (SHG) efficiency of the grown crystal was 0.5 times that of potassium dihydrogen phosphate (KDP) crystal, a promising material in NLO applications.