Structural, electronic and vibrational properties of sulfated β–5 lignin model compounds: a DFT investigation

Using the B3LYP/6-31G(d,p) DFT method, the structural, electronic and vibrational properties of the β–5 lignin model compound and its sulfated derivatives were investigated. The introduction of sulfate groups was found to increase the electrophilicity and chemical softness of the molecules, shift the electron density toward the sulfate groups and create extensive negatively charged regions, thereby enhancing intermolecular interactions and improving solubility. These changes make sulfated lignin derivatives promising for applications in green chemistry, pharmaceuticals and functional biomaterials.