Molecular Engineering to Tune Functionality: The Case of Cl-Substituted [Fe(terpy)].

The properties of transition-metal complexes and their chemical dynamics can be effectively modified with ligand substitutions, and theory can be a great aid to such molecular engineering. In this paper, we first theoretically explored how substitution with a Cl atom at different positions of the terpyridine ligand affects the electronic structure of the [Fe(terpy)] complex. We found that besides the substitution at position 4', the next most promising candidate to cause substantial electronic effects is that where the side pyridine ring is substituted at position 5 (β).