Infrared Spectroscopy of Anionic, Cationic, and Zwitterionic Surfactants

Figure 5

Selected regions of the FTIR spectra for the CTAB molecule. (a) C–H stretching vibrational features; (b) methylene scissoring vibration and asymmetric bending mode of the head [N(CH₃)₃] methyl group. (c) CH₂ wagging region; (d) C–N stretching vibrational modes. The spectra refer to the CTAB packing densities: 1.0×10¹⁵; 3.1×10¹⁵; 6.5×10¹⁶; 2.1×10¹⁷ molecules cm⁻².

(a)

(b)

(c)

(d)