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Stochastic boundary conditions

See Sec. 6.62.5 and 6.62.5 for brief description of stochastic boundary conditions and Langevin thermostat, respectively. Note that geometric constraints and metadynamics are not supported for this simulation protocol.
  1. Set the standard MD-related flags: IBRION=0, TEBEG, POTIM, NSW, ISIF=2
  2. Set MDALGO to 3 to invoke Langevin dynamics 6.62.3.
  3. Prepare the POSCAR file in such a way that the Newtonian and Langevin atoms are treated as different species (even if they are chemically identical)
  4. In POSCAR, use Selective Dynamics and corresponding logical flags to define the frozen and movable atoms
  5. Using LANGEVIN_GAMMA (see 6.62.3), set friction coefficients ($ \gamma$) to zero for all fixed and Newtonian atoms, use proper value of $ \gamma$ for Langevin atoms



N.B. Requests for support are to be addressed to: vasp.materialphysik@univie.ac.at