Quantum chemical calculations are based on the electronic structure of molecules and make use of numerical methods for solving the stationary Schrödinger equation. The results of these calculations allow for the computation of multiple physical and chemical properties of molecules: Heat capacity, heating value, and reaction rates of chemical reactions the molecules might be involved in, to name a few. Among other applicatoins, these properties are used in complex chemical models in order to describe the formation and consumption of chemical compounds.
At our institute, we are using a broad spectrum of software to utilize quantum chemistry. The quantum mechanical software programms Gaussian and Orca are being used to solve the stationary Schrödinger equation numerically. The software programms Tamkin and MESS are using the results of the quantum mechanical calculations to predict rate coefficients of chemical reactions. Special emphasis is put on including pressure-dependency and non-Boltzmann effects. These effects are of particular importance for gas phase chemical reactions.