A density-functional-theory study of biradicals from benzene to hexacene

作者：Kim Hyun Jung; Wang Xingyong; Ma Jing^*; Cho Jun Hyung

来源：Chemical Physics Letters, 2011, 516(4-6): 141-145.

DOI：10.1016/j.cplett.2011.09.087

The singlet-triplet energy gap of biradicals created in benzene and polyacenes is investigated by density-functional-theory calculations. For the biradicals in benzene, naphthalene, anthracene, tetracene, pentacene, and hexacene, we find that the singlet state is energetically favored over the triplet state by 189, 191, 184, 199, 218, and 244 meV, respectively. The monotonous increase of the singlet-triplet energy gap from anthracene to hexacene is attributed to the enhanced stability of the singlet state for longer polyacenes. Our analysis shows that the spin density of the singlet state is delocalized over all benzene rings, but such a spin delocalization is not present for the triplet state.

• 出版日期2011-11-18
• 单位南京大学