Enhancing galactic simulations: Black holes and molecules

We review the modeling of AGN and molecular gas in galaxy simulations. We discuss estimates for the accretion rate of black holes, and present a model that may couple more strongly to the properties of the gas flow. We also present a sub-grid model for the formation of molecular gas for galaxy simulations. We present results of test calculations and discuss their application to galaxy collision simulations, where both ingredients are crucial for an understanding of the merger process.