The polymerization mechanism is then obtained by using the Get Class routine. The Get Mechanism routine recognizes the class name and assigns a pre-defined mechanism. For instance, if the polymer class is identified as "polyamide", the routine assigns the "polycondensation" mechanism to the polymer. This process is straightforward for all classes, except for the vinyl mechanism, in which subcategories exist. For example, a pro-vinyl monomer can polymerize through radical polymerization, cationic polymerization, or anionic polymerization . The likelihood depends on polymerization initiator, solvent, and polymerization stereochemistry.