Phase diagram of the C12E6/D2O system revisited: Effect of strong magneticfields

Lyotropic mixtures composed by heavy water and C12E6 (n-dodecylhexaoxyethyl ene glycol [CH3(CH2)(11)(OCH2CH2-CH2)(6)OH], with different mole ratios, W- 0, have been studied in the presence of high magnetic fields. Depending on both thermal history and magnetic conditioning, a significant orientation o f the samples is obtained and the phase boundaries are slightly modified wi th respect to the originally reported ones. The resulting H-2 spectra show the presence of two components, one iso-oriented and another one partially oriented. To quantify the amount of oriented spectral components a full sim ulation was performed, based on 0th, 2nd, and 4th rank Legendre polynomials . Experimental investigation is focused on the hexagonal mesophase, but inf ormation is also given on the lamellar phase. The iso-orientation of sample s is kept for several months. The presence of a large amount of iso-oriente d phases is confirmed by optical polarizing microscopy experiments.