FluctuatingChargeLangevin.hpp

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 * SUPPORT OPEN SCIENCE!  If you use OpenMD or its source code in your
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 * [1] Meineke, et al., J. Comp. Chem. 26, 252-271 (2005).
 * [2] Fennell & Gezelter, J. Chem. Phys. 124, 234104 (2006).
 * [3] Sun, Lin & Gezelter, J. Chem. Phys. 128, 234107 (2008).
 * [4] Vardeman, Stocker & Gezelter, J. Chem. Theory Comput. 7, 834 (2011).
 * [5] Kuang & Gezelter, Mol. Phys., 110, 691-701 (2012).
 * [6] Lamichhane, Gezelter & Newman, J. Chem. Phys. 141, 134109 (2014).
 * [7] Lamichhane, Newman & Gezelter, J. Chem. Phys. 141, 134110 (2014).
 * [8] Bhattarai, Newman & Gezelter, Phys. Rev. B 99, 094106 (2019).
 */
 
#ifndef INTEGRATORS_FLUCTUATINGCHARGELANGEVIN_HPP
#define INTEGRATORS_FLUCTUATINGCHARGELANGEVIN_HPP
 
#include <random>
 
#include "flucq/FluctuatingChargePropagator.hpp"
#include "utils/RandNumGen.hpp"
 
namespace OpenMD {
 
  class FluctuatingChargeLangevin : public FluctuatingChargePropagator {
  public:
    FluctuatingChargeLangevin(SimInfo* info);
 
    RealType getTargetTemp() { return targetTemp_; }
 
    void setTargetTemp(RealType tt) { targetTemp_ = tt; }
 
    RealType getDragCoefficient() { return drag_; }
 
    void setDragCoefficient(RealType drag) { drag_ = drag; }
 
    int getMaxIterationNumber() { return maxIterNum_; }
 
    void setMaxIterationNumber(int maxIter) { maxIterNum_ = maxIter; }
 
    RealType getForceTolerance() { return forceTolerance_; }
 
    void setForceTolerance(RealType tol) { forceTolerance_ = tol; }
 
  private:
    virtual void initialize();
    virtual void moveA();
    virtual void applyConstraints();
    virtual void moveB();
 
    virtual void updateSizes() {}
    virtual RealType calcConservedQuantity() { return 0.0; }
 
    int maxIterNum_;
    RealType forceTolerance_;
    RealType targetTemp_;
    RealType drag_;
    RealType dt2_;
    RealType dt_;
 
    Snapshot* snap_ {nullptr};
 
    Utils::RandNumGenPtr randNumGen_ {nullptr};
    std::normal_distribution<RealType> forceDistribution_;
  };
}  // namespace OpenMD
 
#endif