Tricriticality in generalized Schloegl models for autocatalysis: Lattice-gas realization with particle diffusion

► We analyze a hybrid of Schloegl's first and second models for autocatalysis. ► The relative strength of the associated particle creation mechanisms is varied. ► A crossover occurs between continuous and discontinuous poisoning transitions. ► This tricritical behavior is assessed by KMC simulation of the lattice model. ► Behavior is also characterized by mean-field type analysis.