Newton-X contains several algorithms to create initial geometries and velocities. They can be randomly generated according to some probability distribution function (PDF) or picked from a previous set of dynamics simulations. The difference between them is discussed in reference [61]. In certain situations, hybrid sampling using trajectories and PDFs may be required. Finally, random velocities corresponding to a predetermined kinetic energy value can be generated for a fixed geometry (the algorithm is described in the appendix of reference [63]).