A graph theoretic model for configurational isomerism
John Wise McLeod · AcadiaU-DEV · 1976
The mathematical definition of a graph is extended to model the chemical concept of configurational isomerism. This extension involves the ordering of the set of neighbors around each vertex of what is called a C-graph. This ordering is thought of as an assignment of a vertex's neighbors to locations in a geometric figure, whose rigid motions determine a group of permutations called the local shape at that vertex. Extensions of graph isomorphism are introduced which partition the class of all C-graphs into equivalence classes corresponding to the structural isomers and configurational isomers of chemistry. Sufficient theoretical machinery is developed to enumerate and simply describe the configurational isomers within a given structural isomer.