Table 2. Number of H-Bond Formation between the NH₂ Group of DOP and qSPC/Fw Water Molecules throughout Multilevel Simulations^a,b.

	QM/MM			MM
donor–H···acceptor	DFT	DFTB	PM3	GAFF(qHF)	GAFF(qDFT)	GAFF(qDFTB)
OWAT–H···NDOP	0.7 (0.3)	0.2 (0.2)	0.3 (0.3)	1.3 (0.3)	0.8 (0.3)	0.3 (0.3)
NDOP–H···OWAT	0.4 (0.3)	0.4 (0.3)	0.2 (0.2)	0.9 (0.5)	0.4 (0.4)	0.4 (0.4)

^aDFT, DFTB, and PM3 stand for the levels of QM theory tested in the QM/MM simulations.

^bAverage standard deviation (SD).