Table 6: Calculated energy of interaction energy without correction ( , kcal/mole), BSSE corrected energy of hydrogen-bond formation using counterpoise correction ( , kcal/mole) for DEG + water complex ( = 1, 2), and DEG dimer using 6-31++G(d,p) basis set and various methods.

Systems Calculation methods

DEG + 1 water complex (GD)MP2−7.24−5.13
WB97XD−7.00−6.09
B3LYP DFT-D−7.28−6.28
M062X−7.41−6.44
M06−6.90−6.01
B3LYP−6.06−5.14
HF−5.20−4.51

DEG + 1 water complex (WD) MP2−7.56−5.53
WB97XD−7.51−6.75
B3LYP DFT-D−8.35−7.51
M062X−7.85−7.05
M06−7.07−6.32
B3LYP−6.19−5.44
HF−5.13−4.59

DEG + 2 water complexMP2−15.08−11.04
WB97XD−14.12−12.60
B3LYP DFT-D−16.64−14.98
M062X−15.61−13.99
M06−14.15−12.65
B3LYP−12.33−10.83
HF−10.23−9.15

DEG dimer complex
MP2−13.93−8.53
WB97XD−9.69−8.71
B3LYP DFT-D−16.08−14.71
M062X−14.80−13.41
M06−13.85−12.55
B3LYP−6.44−5.32
HF−5.04−4.39