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Numerical study of a first-order irreversible phase transition in a CO+NO catalyzed reaction model

Ernesto S. Loscar·Ezequiel V. Albano
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Abstract

The first-order irreversible phase transitions (IPT) of the Yaldran-Khan model (Yaldran-Khan, J. Catal. 131, 369, 1991) for the CO+NO reaction is studied using the constant coverage (CC) ensemble and performing epidemic simulations. The CC method allows the study of hysteretic effects close to coexistence as well as the location of both the upper spinodal point and the coexistence point. Epidemic studies show that at coexistence the number of active sites decreases according to a (short-time) power law followed by a (long-time) exponential decay. It is concluded that first-order IPT's share many characteristic of their reversible counterparts, such as the development of short ranged correlations, hysteretic effects, metastabilities, etc.

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Ernesto S. Loscar, Ezequiel V. Albano. 2002-10-09. Numerical study of a first-order irreversible phase transition in a CO+NO catalyzed reaction model. https://doi.org/10.1103/physreve.65.066101

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