# Table 4 Values of the coupling energy of Phe86 in E9 with Asp33 in Im2

Ratio 1:2:8:2 1:1:4:1 2:1:4:1
Charge state +8 +9 +8 +9 +8 +9
ΔΔG int(ij) (kcal mol−1) 1.08 ± 0.10 1.08 ± 0.05 1.28 ± 0.15 1.27 ± 0.20 1.32 ± 0.16 1.21 ± 0.07
1. Values of the coupling energy, ΔΔG int(ij), were calculated for the charge states +8 and +9 using the concentration ratios 1:2:8:2, 1:1:4:1, and 2:1:4:1 as defined in Fig. 4. Similar coupling energies are obtained for the different concentration ratios