DFT Study of Binding and Electron Transfer from a Metal-Free Dye with Carboxyl, Hydroxyl, and Sulfonic Anchors to a Titanium Dioxide Nanocluster

Table 2

Contributions of various groups, in %, to the electron density of the HOMO and LUMO, calculated at DFT/B3LYP/6-31+G(d) level.

Dye	MO	BSA	–N=N–	SA
H2-ACY^2− (missing H1 and H3)	HOMO	26.73	7.80	65.46
	LUMO	33.96	38.52	27.51
H1H2-ACY^− (missing H3)	HOMO	37.75	7.84	54.41
	LUMO	52.70	19.93	27.37
H1-ACY^2− (missing H2 and H3)	HOMO	49.81	6.72	43.47
	LUMO	46.20	7.20	46.60
H3-ACY^2− (missing H1 and H2)	HOMO	49.80	6.72	43.48
	LUMO	48.43	11.27	40.30
H1H3-ACY^− (missing H2)	HOMO	44.46	11.53	44.01
	LUMO	53.20	21.18	25.62
H2H3-ACY^− (missing H1)	HOMO	38.24	11.49	50.27
	LUMO	38.42	38.08	23.49

BSA: benzenesulfonic acid, SA: salicylic acid.