Rules in EROS

A rule in EROS consists of a global part describing the name, reactors, phases, and kinetics and a reaction part that defines one or more reaction rules. An example of a simple EROS rule for bond formation and cleavage in Tcl looks as follows  

The set functions define the atoms that are centers of reaction. 

The reactant function included information on physicochemical properties for the reaction centers that shall be accounted for. In the upper case, the property 

A QSIG describes the partial atomic sigma charge of reaction center 2, which is assigned to the variable qsige2. 

The reaction generator defines two statements for bond cleavage (1) changing the bond order between reaction centers 1,2 and 3,4 to -1 and (2) the creation of new single bonds indicated by changing the bond order between centers 2,3 and 1,4 to 1. 

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