Ultrasonic Studies in N-(p-n-butoxybenzylidene)-p-n-butylaniline

Abstract

Abstract The ultrasonic velocity in the SG(SH), SB, SA, Nc , N0 and isotropic liquid phases of N-(p-n-butoxybenzylidene)-p-n-butylaniline (BBBA) has been measured as a function of temperature. A transition in the nematic phase seems to indicate the existence of an ordinary nematic and a cybotactic nematic phase. The transition SG-SB has been found for the first time with the ultra-sonic velocity method. The adiabatic compressibility βad and the molar sound velocity Rn (Rao number) have been determined using the experimental density and ultrasonic velocity.