Density of methoxybenzylidene butylaniline about the isotropicndash;nematic phase transition

摘要

We have measured the density and determined the coefficient of expansion of MBBA about its isotropicminus;nematic transition temperature using a Mettler/Paar density meter. Our results show essential agreement with those of Press and Arrott using a buoyancy method. The small difference (0.3deg;C) between the actual transition temperature and the virtual critical temperature differs from that determined by light scattering studies which yield values of about 1deg;C. Further examination on the nature of the virtual critical temperature is suggested.