. 2010 May 3;11(5):2017–2038. doi: 10.3390/ijms11052017

Table 4.

AIM analysis of studied flavonoids monomers computed in gas phase at the B3LYP/6-311++G** theoretical level. Electron density at BCP, ρ_BCP; Laplacian of electron density at BCP, ∇² ρ_BCP; donor–acceptor interatomic distance, r, and angle, ϕ, for the intramolecular H-bonds. Values calculated for optimized structures reported in Figure 2. Intramolecular H-bonding sites defined in Figure 4. ϕ is defined ad D-H---A, where it stands for O-H---O(C) for HB_1 and HB_2, C-H---O(H) for HB_3, and O-H---H(O) for HB_4 and HB_5.

Comp.	H-bond	ρ_BCP/a.u.	∇²ρ_BCP/a.u	r/Å	ϕ/deg	Comp.	H-bond	ρ_BCP/a.u.	∇²ρ_BCP/a.u	r/Å	ϕ/deg
I	HB 1	0.044	0.128	1.74	146.9	XII	HB 1	0.038	0.119	1.80	145.7
II	HB 1	0.044	0.128	1.74	146.9		HB 2	0.026	0.103	2.02	117.7
III	HB 1	0.044	0.128	1.74	147.0		HB 3	0.018	0.076	2.13	122.6
IV	HB 1	0.044	0.128	1.74	146.8	XIII	HB 1	0.038	0.120	1.80	145.9
V	HB 1	0.044	0.128	1.74	147.0		HB 2	0.026	0.100	2.02	118.0
V	HB 5	No	No	2.16	112.0		HB 3	0.018	0.076	2.15	123.3
VI	HB 1	0.044	0.128	1.74	146.8		HB 5	No	No	2.17	112.1
VII	HB 1	0.044	0.128	1.74	147.0	XIV	HB 1	0.038	0.120	1.80	145.6
VII	HB 4	No	No	2.15	112.3		HB 2	0.026	0.103	2.01	118.2
VIII	HB 1	0.044	0.128	1.74	147.0		HB 3	0.018	0.074	2.13	123.9
	HB 4	No	No	2.21	110.3	XV	HB 1	0.039	0.120	1.80	145.9
	HB 5	No	No	2.21	111.7		HB 2	0.026	0.104	2.02	118.1
IX	HB 1	0.038	0.119	1.80	145.8		HB 3	0.018	0.075	2.13	124.0
	HB 2	0.026	0.104	2.02	117.9		HB 4	No	No	2.15	112.4
	HB 3	0.018	0.076	2.15	123.8	XVI	HB 1	0.039	0.119	1.80	145.8
X	HB 1	0.038	0.120	1.80	145.7		HB 2	0.026	0.103	2.02	118.3
	HB 2	0.026	0.104	2.02	118.0		HB 3	0.018	0.074	2.13	123.7
	HB 3	0.018	0.072	2.16	123.4		HB 4	No	No	2.21	110.5
XI	HB 1	0.039	0.120	1.79	145.9		HB 5	No	No	2.21	111.9
	HB 2	0.026	0.100	2.03	117.8
	HB 3	0.018	0.076	2.15	123.5