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

TL;DR

This paper investigates the first-order irreversible phase transition in a CO+NO catalytic reaction model using the constant coverage ensemble and epidemic simulations, revealing characteristics similar to reversible transitions.

Contribution

It introduces the use of the constant coverage ensemble and epidemic simulations to study the IPT in the Yaldran-Khan model, highlighting hysteresis and metastability features.

Findings

Hysteretic effects observed near coexistence

Active sites decay exponentially at long times

Short-range correlations develop during transition

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.