The purpose of the project is the simulation of radiative association in molecular collisions with interstellar relevance. In the project we use our home-built quasiclassical trajectory (QCT) code. In the QCT method the fragments before the collision are prepared in a semiclassical quantum state and the classical equations of motion are solved for the nuclei to simulate the collisions. In the QCT procedure we use a Monte Carlo estimation of the cross sections, thus the initial semiclassical rovibrational states of the molecules are prepared in a random way. Due to the Monte Carlo procedure the calculation of the collision processes are quasiparalell: each individual collision can be calculated independently.