Energy band gap properties of 3a–3d.

Compounds	HOMOa (eV)	LUMOb (eV)	E ex (eV)	HOMOc (eV)	LUMOc (eV)	E cal (eV)
3a	−5.94	−3.89	2.05	−4.88	−2.19	2.69
3b	−5.93	−3.90	2.03	−4.79	−2.12	2.67
3c	−5.86	−3.89	1.97	−4.70	−2.09	2.61
3d	−5.78	−3.87	1.91	−4.55	−2.05	2.50

^a E _HOMO (eV) = −e(E^OX_onset + 5.2).

^bE_LUMO (eV) = −e(E^red_onset + 5.3).

^cObtained by DFT calculation.