Ratelikningerne

Ratelikningerne, also known as the Ratel equations, are a set of differential equations used in computational chemistry and physics to model the dynamics of chemical reactions. They were developed by the theoretical chemist Arthur Ratel in the late 20th century. The core idea behind these equations is to describe the evolution of the concentrations of reactants and products over time, taking into account the rates of elementary reaction steps.

The Ratel equations are typically derived from a proposed reaction mechanism, which breaks down a complex overall reaction into a series of simpler, reversible or irreversible steps. For each elementary step, a rate law is defined, usually based on the law of mass action, which relates the rate of the step to the concentrations of the reacting species. By applying these rate laws and considering the stoichiometry of each step, a system of coupled ordinary differential equations is constructed.

Solving the Ratel equations allows researchers to predict how the concentrations of all species involved in a reaction will change over time under specific conditions, such as initial concentrations and temperature. This can provide insights into reaction pathways, intermediate species, and the overall kinetics of the process. The equations are particularly useful for studying complex reaction networks where simple analytical solutions are not feasible. They form a fundamental tool in areas like chemical kinetics, combustion modeling, and atmospheric chemistry.