Clarify chemical species representation in CDIMA model documentation: specify dimensionless concentrations of I$^-$ and ClO$_2^-$.

Author: Daniel Precioso, PhD

modules/ode-2d/cdima.qmd

@@ -12,7 +12,7 @@ $$\begin{aligned}
 \dot y &= bx \left( 1 - \frac{y}{1+x^2} \right)
 \end{aligned}$$
 
-where $x$ and $y$ represent concentrations of chemical species, and $a,b$ are parameters controlling the reaction rates [@strogatz2024nonlinear, Chapter 8.3].
+where $x$ and $y$ are the dimensionless concentrations of I$^-$ and ClO$_2^-$. The parameters $a,\ b > 0$ depend on the empirical rate constants and on the concentrations assumed for the slow reactants [@strogatz2024nonlinear, Chapter 8.3].
 
 ## Phase-Plane Analysis