Table 1.

Computational and optical data

	Computational			Optical
Compound	E HOMO	E LUMO	E gap	λ max	λ edge	E gap
2	−5.98	−2.19	3.79	329	345	3.59
IF	−5.42	−3.17	2.25	507	534	2.33
6,12-Dimesityl-IF18	−5.32	−3.15	2.17	51618	54118	2.2918

Hybrid functional HSE (Heyd, Scuseria and Ernzerhof)^{54, 55} with a mixing coefficient of 0.3 was applied for computational calculations. Wavelengths λ_max and λ_edge are in nm and energies E_HOMO, E_LUMO and E_gap are in eV