Synthesis, Quantum Chemical, Spectral, Optical, Thermal and Biological Studies on Sulfamethazine Single Crystal

The single crystal of the pharmaceutical drug sulfamethazine has been grown using the slow evaporation method at ambient temperature. The analysis of the single crystal X-ray diffraction (XRD) data indicates that the grown crystal belongs to the monoclinic crystal system. This classification is based on the symmetry and the lattice parameters observed during the single crystal XRD analysis. The optimized geometry of sulfamethazine molecule was determined using two methods viz. density functional theory (DFT) and restricted Hartree-Fock (RHF) in the gas phase. Spectral analysis of grown crystal was performed, offering an examination of its vibrational modes and providing the functional groups of the compound. The Mulliken atomic charge distribution was also computed to provide information about the electron density distribution across the molecule, highlighting the nature of charge transfer between atoms. Sulfamethazine crystals demonstrate high transmittance in the 190-1100 nm range, as observed in the UV-visible spectrum. The thermal behavior of the studied compound was examined through TGA/DTA analysis and revealed that the crystal maintains thermal stability up to 210 ºC. The sulfamethazine aslo exhibit significant antibacterial effects against bacterial species such as Escherichia coli and Staphylococcus aureus, highlighting their potential as an effective antimicrobial agent.