The Chemical Evolution of Protoplanetary Disks

The origins of planets, and perhaps life itself, is intrinsically linked to the chemistry of planet formation. In this chapter we will attempt to explore the chemistry of planet-forming disks from the perspective of knowledge gained from decades of solar system study, combined with our rapidly growing knowledge of extra-solar protoplanetary disks. Our aim is not to provide a comprehensive survey of the literature, but rather to present the chemical and physical tools that are used to explore chemical evolution during the earliest stages of planet formation. We include a discussion of observational constraints from our solar system and extra-solar disks, thermodynamic equilibrium and chemical kinetics, and the physical prescriptions for various important aspects (X-ray/UV irradiation, thermal structure, molecular adsorption/desorption, ..) that are used in current models. The chapter is aimed for young researchers.