The MD method is deterministic in which the state of the system at any time are predictable once positions and velocities of each atom are known. MD simulations are sometime time consuming and computational expensive. Nevertheless, the faster and cheaper of the computer today bring up the calculation to the nanosecond time scale.
The basic step in MD simulation was shown in Figure 3.2 The initial system, in which the coordinated can be normally obtained from x-ray or NMR data or built up using molecular modeling method, is minimized in order to get rid of bad atomic contacts due to the addition of some newly atoms and residues, i.e., hydrogen atoms, amino acid residues as well as water molecules. The initial velocities of the system were assigned to the system. Prior to the production dynamics, the heating and equilibration dynamics were performed with the aim to decreases the probability that localized fluctuations in the energy such as hot spots in which will persist throughout the simulation. Following the initial thermalization/equilibration, some more period of time for equilibrations were applied until the system is reached the equilibrium by adjusting the temperature and rescaling the velocities. The trajectory of the systems is calculated and used for analysis.