• A. Martínez-Richa Facultad de Química, Universidad de Guanajuato.
  • E. García-Sánchez Facultad de Química, Universidad de Guanajuato.
  • D. C. Williamson Facultad de Química, Universidad de Guanajuato.
Keywords: convex-peg model, isotropic-nematic transition, perturbation theory, liquid crystals


In this work a first-order Barker-Henderson perturbation theory for the “Convex Peg” model is presented. The long -range approximation of Ponce and Renon for the spherical square-well fluid is used in conjunction with Parsons decoupling approximation. The theory is extended to include the nematic phase. For the phase diagram, a vapour-liquid-nematic triple point is predicted below which the nematic phase coexists with the vapour phase. The “Convex Peg” model is used to predict the Isotropic-Nematic transition for p-azoxyanisole (PAA). Thermodynamic properties are predicted with good accuracy. Limitations of the present model in the prediction of thermodynamics properties of real liquid crystal systems are discussed.


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How to Cite
Martínez-Richa, A., García-Sánchez, E., & C. Williamson, D. (2020). THE “CONVEX-PEG” MODEL APPLIED TO p-AZOXY-ANISOL. Revista Mexicana De Ingeniería Química, 2(1), 35-41. Retrieved from