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

Table 3

Calculated hydrogen-bond distances (d_O⋯H, Å), hydrogen-bond angles (A_O⋯H-O, degree), and dipole moment (𝐷, debye) for single TEG and TEG + 𝑛_𝑤 water complex (𝑛= 1, 2, 4) using 6-31++G(d,p) basis set and various methods.

System	Parameters	Methods
		MP2	WB97XD	B3LYP; DFTD	MO62X	MO6	B3LYP	HF
TEG	𝐷	2.58	2.34	2.43	2.31	2.46	2.41	2.42
TEG + 1 water complex (GD)	dO⋯H,; O25...H15	1.94	1.90	1.89	1.94	1.93	1.92	2.04
	AO⋯H,; O25⋯H15–O6	173.13	172.71	175.39	159.79	164.13	177.01	178.10
	𝐷	4.61	4.30	4.33	4.51	4.61	4.08	4.18
TEG + 1 water complex (WD)	dO⋯H,; O6⋯H25	1.90	1.88	1.85	1.90	1.913	1.89	2.02
	AO⋯H,; O6⋯H25–O26	160.76	162.44	162.64	153.65	154.59	165.46	168.99
	𝐷	1.72	1.56	1.5	1.76	1.77	1.56	1.94
TEG + 2 water complex	dO⋯H,; O25⋯H15	1.94	1.90	1.89	1.94	1.93	1.92	2.04
	dO⋯H,; O28⋯H23	1.92	1.89	1.87	1.90	1.92	1.91	2.04
	AO⋯H,; O25...H15–O6	173.07	174.19	175.47	160.52	164.03	176.55	178.99
	AO⋯H,; O28⋯H23–O22	179.34	178.75	176.76	171.22	161.78	175.54	179.45
	𝐷	5.40	4.80	4.64	5.66	5.80	4.08	4.69