# 12.3. Variable Rate Constant Model¶

## 12.3.1. Description¶

Volume molecules vm are placed inside a cube and disappear accordingly to the following reaction (vm -> NULL). The rate constant of this reaction is variable, it is given by the text file rate_constant.txt, it is zero before time step $$5.10^{-4}$$ s and $$1.10^{4} s^{-1}$$ afterwards.

## 12.3.2. Demonstrated features¶

• A variable rate constant is implemented in this example.