Table 2. The effect of solvent on the rates of the slower steps in the Pr → Pfr photoconversion.

Step	Relative amplitude	σ (cP)	Rate (s−1)
			H2O	5% ethanol	5% isopropanol	35% sucrose
1st	17%	1.26±0.29	3235±400	3100±195	3040±265	1365±80
2nd	26%	2.89±0.72	368±60	328±47	314±39	205±41
3rd	38%	0.77±0.19	45.9±1.8	40.0±2.9	36.6±3.1	16.4±0.8
4th	19%	>40	2.22±0.28	2.01±0.22	1.96±0.21	2.02±0.05

The rate and amplitude of each step was measured at 293 K (Materials and Methods). The degree of solvent-coupled dynamics (σ) required for each step were obtained by fitting the viscosity-dependence of the rates to equation 2 (Figure 7).