753139.fig.005a
(a)
753139.fig.005b
(b)
753139.fig.005c
(c)
753139.fig.005d
(d)
753139.fig.005e
(e)
753139.fig.005f
(f)
Figure 5: Calculated energy (kcal/mol) curve using WB97XD/6-31++G(d,p) of for (a) a free bond of O–H ( ) group of DEG, (b) hydrogen-bonded O–H ( ) group of DEG + 1 water complex (GD), (c) a free bond of O–H ( ) group of triethylene glycol (TEG), (d) hydrogen-bonded O–H ( ) group of triethylene glycol + 1 water complex (GD), (e) a free bond of O–H ( ) group of dipropylene glycol (DPG), and (f) hydrogen-bonded O–H ( ) group of DPG + 1 water complex (GD).