14N NMR spectra of molecular nitrogen in SDS/pentanol swollen lamellar phases.
14N NMR spectra of air dissolved in lyotropic mesophases are reported. In order to observe the whole spectrum from a molecule in which the quadrupole coupling constant is on the order of a few megahertz, a weak alignment degree with respect to the magnetic field is mandatory. Therefore, dilute lyotropic liquid crystals, namely sodium dodecylsulphate (SDS)/pentanol swollen lamellar phases, were considered. The temperature dependence of the 14N quadrupolar splitting was followed both in the case of oil (either n-dodecane or n-heptane) and brine (a 0.2-M NaBr water solution) swelling. In the former, it paralleled the temperature dependence of the splittings of the alkane deuteria and, in both cases, it was opposite to 23Na quadrupolar splittings. Owing to the higher N2 solubility in hydrocarbons, the 14N NMR spectra provide complementary information to that obtained by means of the quadrupolar nuclei of water and hydrophilic solutes.
Dipartimento di Scienze Chimiche, Università di Trieste, via L. Giorgieri 1, I-34127 Trieste, Italy. gpellizer@units.it
Giorgio
G
Pellizer
Fioretta
F
Asaro
D050866:Liquid Crystals; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D009584:Nitrogen / Q000737:chemistry*; D009587:Nitrogen Isotopes; D000439:Pentanols / Q000737:chemistry*; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry*; D013696:Temperature
D009587:Nitrogen Isotopes; D000439:Pentanols; D012967:Sodium Dodecyl Sulfate; D009584:Nitrogen