Calculating stabilization energies for aromatic molecules in schools – quantum chemistry, a valuable tool for teaching and education

Abstract

While aromaticity is one of the most fundamental concepts in chemistry and is taught in many elementary organic chemistry courses, it is hardly possible to activate pupils and students to learn and explore this topic independently. By applying computational chemistry and especially quantum chemistry, we introduce a possibility to activate students, allowing them to test taught concepts and do their own “experiments” cheaply and securely. We have focused in the current report on the structural and energetic aspects of aromaticity, as they are most compatible with other topics of typical chemistry lessons. To evaluate the aromatic stabilization energy, we suggest the simple-to-calculate and easy-to-understand isomerization stabilization energy (ISE) popularized by Paul von Ragué Schleyer and Frank Pühlhofer some 20 years ago. As practical examples, we demonstrate our concept with benzene- and pyridine-based systems and suggest topics for small projects for students and pupils.