HOMO and LUMO energies, and band gaps (in eV) at CAM-B3LYP/6-311++G**.

	HOMO	LUMO	ΔEL→H
1a	−8.81	−1.93	6.88
1b	−8.56	−1.81	6.75
1c	−8.22	−1.73	6.49
1d	−6.87	−1.90	4.97