Nuclear Magnetic Resonance Investigation of a Sodium Dibutyl Phosphate/Water Lyotropic Mesophase

Article abstract of DOI:10.1021/j100245a001

2H and 31P NMR have shown that concentrated aqueous solutions of sodium dibutyl phosphate (NaDBP) give rise to a lamellar mesophase for NaDBP mole fractions varying from 0.1 to 0.2 in a temperature range T=285-340 K.By cooling the samples from the isotropic phase in a magnetic field the formation of a discotic DM II mesophase is observed.Different models of water reorientation are proposed to account for the 2H and 17O quadrupole splittings.Nuclear relaxation experiments show that, in this particular system, water molecules reorient preferentially about the direction of an oxygen lone pair orbital.