Table 9. Water Bridge Occupancies for 1–9 Obtained from HREX Simulations^a.

compound	O5···O6	O6···O5′	O5···O5′	O5···O2′	O5···HO2′	O6···O2′	HO4···O2′	O6···O=C
1	0.25		0.00
2	0.30	0.18	0.08					0.15
3	0.41	0.19	0.11	0.16		0.17	0.11
4	0.29		0.00	0.26	0.25	0.22
5	0.32	0.18	0.11	0.13		0.14	0.11
6			0.00			0.15
7		0.18	0.02					0.11
8	0.26	0.15	0.11			0.14
9	0.26		0.00	0.22	0.17	0.24

^aH-bond occupancies of >0.08 are shown. The BRIDge option in CHARMM was used for calculating the average number of water bridges formed between selected pairs of atoms.