The Effect of the Initial Structure on the System Relaxation Time in Langevin Dynamics
Abstract
In recent decades, computer experiments have allowed an accurate and fundamental understanding of molecular mechanisms at the microscopic level, such as the process of relaxation at a stable physical state. However, computer simulations may sometimes produce non-physical results or relations due to the incompleteness of mathematical models describing physical systems. In this thesis, we have investigated whether the initial structure in a computer simulation affects the system relaxation time, which is denoted by τsys, in the Langevin NVT ensemble. We found that for an initial structure, which is inhomogeneous in the number density of atoms, the system relaxation time, τsys, is longer, often by more than an order of magnitude, compared to that for the homogeneous initial structure. Moreover, we realized that the system relaxation time for the inhomogeneous initial structure is an increasing function of the Langevin coupling constant γ.