Amide bands in infra-red spectra: the direction of the transition moments of bands in N,N' -diacetylhexamethylenediamine

Results of crystallographic structural analysis are briefly summarized, and are used in conjunction with infra-red dichroic measurements to ascertain the direction within the molecule of the transition moments of infra-red bands. Bands affected by deuteration of the amide groups are assigned to vibrations of the 'amide’ portion of the molecule, and those unaffected by deuteration are assigned to vibrations of the hexamethylene chain and methyl groups. In a few cases the origin of a band is disclosed by the direction of its transition moment.