Conformational, vibrational, NMR and DFT studies of N-methylacetanilide

► FTIR, FT-Raman and NMR spectral studies of N-methylacetanilide were carried out. ► The non-hydrogen atoms excluding the phenyl group are almost coplanar. ► The CNC angle reveals less steric hindrance and more stability in cis- isomer. ► The ELUMO − EHOMO orbital energy gap in case of cis- isomer is found to be 5.8753 eV. ► The nN → πCO∗ interaction has strong stabilisation energy of 61.53 kJ mol−1.