Modeling triangular boron carbon nitrides presents challenges, particularly due to the scarcity of experimental spectroscopic data. In this study, we start focusing on the two 3T boroncentered triangulenes shown in Fig. . Although 3T-a is not expected to violate Hund's multiplicity rule, experimental absorption spectra are available and can be used to parameterize and validate the PPP model. Conversely, 3T-b is expected to exhibit a negative ∆E ST , 71 but, to the best of our knowledge, no experimental spectroscopic data exist for it.