Stability Analysis and Frontier Orbital Study of Different Glycol and Water Complex

Table 10

Calculated deformation energy (Δ𝐸_def, kcal/mole) and relaxation energy (Δ𝐸_relax, kcal/mole) for DEG + 𝑛_𝑤 water complex (𝑛_𝑤 = 1, 2), DEG dimer using 6-31++G(d,p) basis set and various methods (for dimer two values of Δ𝐸_def are given for individual DEG molecule).

Systems	Calculation methods	Δ𝐸def	Δ𝐸relax
DEG + 1 water complex (GD)	WB97XD	0.05	0.05
	B3LYP DFT-D	0.10	0.10
	M062X	0.08	0.06
	M06	0.17	0.17
	B3LYP	0.09	0.09
	HF	0.04	0.05
DEG + 1 water complex (WD)	WB97XD	0.07	0.14
	B3LYP DFT-D	0.11	0.20
	M062X	0.10	0.14
	M06	0.16	0.24
	B3LYP	0.08	0.15
	HF	0.05	0.07
DEG + 2 water complex	WB97XD	0.09	0.23
	B3LYP DFT-D	0.22	0.39
	M062X	0.24	0.32
	M06	0.25	0.40
	B3LYP	0.16	0.29
	HF	0.09	0.13