Density functional calculations of vibrational wavenumbers, ring puckering, and asymmetric CHO potential functions for cyclobutanecarboxaldehyde: comparative study between theoretical and experimental spectra

摘要: Abstract The structural parameters and energies of the trans -equatorial gauche conformers cyclobutanecarboxaldehyde c -C 4 H 7 –CHO were investigated by quantum mechanical DFT-B3LYP (Density Functional Theory-Becke 3 exchange Lee-Yang–Parr correlation functional) calculations using 6-311G ∗∗ basis set. potential functions for CHO asymmetric torsion in equatorial molecule ring puckering inversion derived. vibrational wavenumbers calculated energy distributions PED among symmetry coordinates normal modes computed two stable molecule. assignments on values compared to reported ones from experimental data. infrared Raman spectra mixture plotted line intensities corresponding ones.