Investigating the prototropic tautomerism in (E)-2-[(4-fluorophenyl)iminomethyl]-5-methoxyphenol compound for solid state and solvent media by experimental and quantum computational tools

► Prototropic tautomerism was investigated. ► Investigation of tautomerism was performed depending on solute-solvent interactions. ► Transition structure was also considered in DFT (B3LYP) calculations for proton transfer process.