TABLE 1.

Parameters of the permeation model (Scheme 2)

Rate constant k(i,j) at 0 mV*	Value
(0,1); (2,3); (4,5)	1×1010 s−1
(1,0); (3,2); (5,4)	3×1010 s−-1
(0,2); (1,3)	9.9×107 s−1
(2,0); (3,1)	7.9×109 M−1s−1
(1,6)	3×109 s−1
(6,1)	7.9×109 s−1
(6,2); (7,4)	6.3×107 s−1
(2,6); (4,7)	9.9×108 M−1s−1
(2,4); (3,5); (6,7)	4×108 M−1s−1
(4,2); (5,3); (7,6)	1×104 s−1

The voltage dependence (z_ij) of each rate constant is indicated in the legend in Fig. 4. Rate constants for transitions between states i and j are given by:

^*The numbering of states is indicated in Scheme 2 (Fig. 4).