Circularly conjugated compounds with 4n+2 pi-electrons are known as aromatic compounds. They are generally stable and are found in our surroundings. Conversely, anti-aromatic compounds with 4n pi-electrons have been conventionally considered unstable, and the creation of stable anti-aromatic compounds has been one of the challenging issues in organic chemistry.
Click here for original story, A demonstration of substituent effects in anti-aromatic compounds
Source: Phys.org