A new variation of the temperature programmed molecular dynamics (TPMD) algorithm, called finite-time TPMD (FT-TPMD), is presented. In this variation, a collection of independent molecular dynamics (MD) trajectories is generated, such that each trajectory is of a fixed duration of time and a transition from a given state of the system may/may not occur in a trajectory. This eliminates the requirement of a successful transition in each trajectory and on-the-fly detection of transitions needed in previous TPMD implementations. As a result, FT-TPMD can be easily implemented with standard MD packages, such as LAMMPS, for performing TPMD calculations. Compared to previous TPMD algorithm, FT-TPMD is shown to be computationally as efficient in some cases and better in others. In addition, several refinements are discussed that enable systematic detection of rare transition events, classification of states, and calculation of rate constants. A set of rules is devised to identify one or more atoms involved in a transition and disqualify recrossing events.

提出了一种新的程序升温分子动力学算法（TPMD），称为有限时间TPMD（FT-TPMD）。在该变型中，产生独立分子动力学（MD）轨迹的集合，使得每个轨迹具有固定的持续时间，并且在轨迹中可以/可以不发生从系统的给定状态的转变。这消除了在每个轨迹中成功过渡的需求，并且无需动态检测先前TPMD实现中所需的过渡。结果，FT-TPMD可以很容易地通过标准MD软件包（例如LAMMPS）实现，以执行TPMD计算。与以前的TPMD算法相比，在某些情况下FT-TPMD在计算上是有效的，而在其他情况下则更好。此外，讨论了一些改进方案，这些改进方案可以对稀有过渡事件进行系统检测，状态分类以及计算速率常数。设计了一组规则以识别涉及过渡的一个或多个原子并取消重新穿越事件的资格。