Handling of aromaticity
The purpose of this section is to give an overview of how Open Babel handles aromaticity. Given that atoms can be aromatic, bonds can be aromatic, and that molecules have a flag for aromaticity perceived, it's important to understand how these all work together.
How is aromaticity information stored?
Like many other toolkits, Open Babel stores aromaticity information separate from bond order information. This means that there isn't a special bond order to indicate aromatic bond. Instead, aromaticity is stored as a flag on an atom as well as a flag on a bond. You can access and set this information using the following API functions: