Ground state analysis of magnetic nanographene molecules with modified edge

We study spin states of edge modified nanographene molecules with rectangular and triangular shapes by first principle calculations using density functional theory (DFT) and Hartree-Fock (HF) methods with Møller-Plesset (MP) correlation energy correction at different levels. Anthracene (C ₁₄H₁₀) and phenalenyl (C₁₃H₉), which contain three benzene rings combined in two different ways, can be considered as fragments of a graphene sheet. Carbon-based ferromagnetic materials are of great interest both in fundamental science and technological potential in organic spintronics devices. We show that non-magnetic rectangular molecules such as C₁₄H₁₀ can become ferromagnetic with high-spin state as the ground state by dihydrogenization of one of the zigzag edges, while triangular molecules such as C₁₃H₉ become ferromagnetic with high-spin state by dehydrogenization of one of the zigzag edges.