Figure 1.

Stopped‐flow signals at 505 nm in a solution of B⁺ and CB7 after mixing with AH⁺ solution in the presence of 0, 0.32, 0.53, 1.0, 1.6, 2.7 and 4.4 mm CaCl₂ (from top to bottom). Total concentrations at t=0 s were [B⁺]_T=[CB7]_T=0.25 μm and [AH⁺]_T=5 μm. Excitation occurred at 345 nm. The black lines represent the result of the nonlinear least‐squares analysis.