RRESPA algorithm

In the rRESPA algorithm, the above factorization is employed together with an integration of each part of the Liouville operator with a different time step. In addition, the forces F are also decomposed into fast (short-range) forces F, and slow (long-range) forces F, according to... 

The heart of the rRESPA algorithm is that the equations of motion are integrated by using two different time steps, it is therefore a Multiple Time Step (MTS) method the slow modes (slow forces, 2X3) are integrated with a larger time step. At, whereas the fast modes (fast forces and velocities, 2X1, 2X2) with a smaller time step, St(St = Atjri). In this case the evolution operator becomes [16]... 

For MD simulations in NVT ensemble, a modification of the rRESPA algorithm has been proposed. The method uses a modification of the Lagrangian of the system based on the Nose-Hoover approach, described in Section III.A. The difference from the standard rRESPA scheme described before is that now the total Liouville operator is decomposed as... 

Based on the previous factorization a very efficient algorithm can be developed, through the use of different time steps for integrating the different parts of the Liouville operator. This is the so-called reversible REference System Propagator Algorithm (rRESPA). 

PC-SAFT Perturbed-chain statistical associating fluid theory rRESPA Reversible reference systems propagator algorithm SAET Statistical associating fluid theory... 

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