On the minimal energy of unicyclic Hückel molecular graphs possessing Kekulé structures Original Research Article

Let image be any unicyclic Hückel molecular graph with Kekulé structures on image vertices where image is an even number. In [W. Wang, A. Chang, L. Zhang, D. Lu, Unicyclic Hückel molecular graphs with minimal energy, J. Math. Chem. 39 (1) (2006) 231–241], Wang et al. showed that if image satisfies certain conditions, then the energy of image is always greater than the energy of the radialene graph. In this paper we prove that this inequality actually holds under a much weaker condition.