P–V Criticality of an AdS Black Hole in f(R) Gravity

We study the thermodynamics of a charged AdS black hole in the special f(R) correction with the constant Ricci scalar curvature. Our results show that the f(R) correction influences the Gibbs free energy and the phase transition of system. The ratio ρ_c occurring at the critical point increases monotonically with the derivative term f'(R₀). We also disclose that the critical exponents are the same as those of the liquid-gas phase transition in the van der Waals model, which does not depend on the f(R) correction considered here.