The low-energy states and electronic spectrum in the near infrared-visible region of [FeC6H6](+) are studied by theoretical approaches. An exhaustive exploration of the potential energy surface of [FeC6H6](+) is performed using the density functional theory with proper functional and basis sets. The structures of the lowest energy states ((4)A(2) and (4)A(1)) are used to perform multireferential wave function calculations by means of Multi-State Complete Active Space with Perturbation at the Second Order method. Contrary to the density functional theory results ((4)A(1) ground-state), multireferential perturbative calculations show that the (4)A(2) state is the ground-state. The vertical electronic spectrum is computed and compared the astronomical Diffuse Interstellar Bands, a set of near infrared-visible bands detected on the extinction curve of our galaxy. Many transitions are found in this domain, corresponding to d -> d, d -> 4s or d -> pi* excitations, but few are allowed and if they are, their oscillation strengths are small. Given the position of the bands and their weak intensities, the contribution of the [FeC6H6](+) complexes to the Diffuse Interstellar Bands is questionable. This work however lays the foundation for the studies of polycyclic aromatic hydrocarbons complexed to Fe cations that are more likely to possess intense d -> pi* and pi -> pi* transitions in the Diffuse Interstellar Bands domain. PAR ligands indeed possess a larger number of pi and pi* orbitals, respectively, higher and lower in energy than those of C6H6, which are expected to lead to lower energy d -> pi* and pi -> pi* transitions ih [FePAH](+) than in [FeC6H6](+) complexes.