Theoretical and ATR-FTIR study of free 12-crown-4 in aqueous solution

► Determination of the geometries of 12c4(aq). ► Population of 12c4(aq) conformers. ► ATR-FTIR spectra of 12c4(aq). ► Distributional treatment of peak analysis for ATR-FTIR. ► Dipole moment of 12c4(aq).