Table 3.

Comparison of electronic properties of DAHA attained experimentally and calculated by TD-DFT/B3LYP method

Solvents	Experimental	TD-DFT B3LYP /6-311++G(d,p)
	Wavelength λmax (nm)	Wavelength λmax (nm)	Band gap (eV)	Energy (cm−1)	Oscillatory strength (f)	Assignments
Gas	–	204	6.08	49061.87	0.01	H→L+2(91%)
		229	5.38	43356.31	0.01	H→L+1(68%)
		211	5.89	47474.58	0.01	H-1→L(41%)
DMSO	–	221	5.61	45217.84	0.02	H→L+1(75%)
		196	6.31	50928.24	0.01	H→L+3(71%)
		198	6.27	50574.16	0.01	H→L+2(25%)
Methanol	256	221	5.61	45210.58	0.02	H→L+1(75%)
		196	6.31	50912.92	0.01	H→L+3(71%)
		198	6.27	50550.77	0.01	H→L+2(25%)