| Abstract
| - High-resolution molar volume data for 4-cyano-4‘-n-octylbiphenyl (8CB) are presented as a function oftemperature near the nematic to isotropic (NI) phase transition. Close to the NI transition the volume wasmeasured at 10 mK temperature steps and at two different pressures. From the data an isobaric thermalexpansion coefficient, αp(T), and isothermal compressibility coefficient, βT(T), were calculated. Fitting theV(T) and βT(T) data according to a tricritical hypothesis with the critical exponents α = α‘= 1/2 allowed oneto find the spinodal temperatures, T* and T**, on both sides of the first-order phase transition. A universalratio (TNI − T*)/(T** − TNI) is compared with the theoretical mean field value. The measured volume jumpat the transition, ΔVNI, is related to the enthalpy jump, ΔHNI, which was obtained from the very precisecalorimetric measurements by other authors.
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