ImprovedDimer.h

Go to the documentation of this file.

/*
** This file is part of eOn.
**
** SPDX-License-Identifier: BSD-3-Clause
**
** Copyright (c) 2010--present, eOn Development Team
** All rights reserved.
**
** Repo:
** https://github.com/TheochemUI/eOn
*/
#pragma once
#include "Eigen.h"
#include "EonLogger.h"
#include "LowestEigenmode.h"
#include "Matter.h"
#include "Parameters.h"
#include <vector>
 
namespace eonc {
 
// dimer method to find the lowest curvature mode
class ImprovedDimer : public LowestEigenmode {
 
private:
  eonc::log::Scoped log;
  // For use when called as part of the NEB-MMF
  VectorXd fixedReferenceMode;
  bool hasFixedReference = false;
 
public:
  // Optimization for the dimer
  //    static const string OPT_SD;
  //    static const string OPT_CG;
  //    static const string OPT_LBFGS;
  static const char OPT_SD[];
  static const char OPT_CG[];
  static const char OPT_LBFGS[];
 
  ImprovedDimer(std::shared_ptr<Matter> matter, const Parameters &params,
                std::shared_ptr<Potential> pot);
  ~ImprovedDimer() = default;
 
  void compute(std::shared_ptr<Matter> matter, AtomMatrix initialDirection);
  double getEigenvalue();
  AtomMatrix getEigenvector();
 
  std::shared_ptr<Matter> x0; // Center image
  std::shared_ptr<Matter> x1; // Forward image
  VectorXd tau;               // Dimer direction
  VectorXd theta;             // Dimer rotation direction
  VectorXd F_R;               // Dimer rotational force
  double C_tau{0.0};          // Curvature along tau
  // For use when called as part of the NEB-MMF
  void setReferenceMode(const VectorXd &ref);
  void clearReferenceMode();
  bool rotationDidConverge{false};
  bool foundNegativeCurvature{false};
  // parameters used for conjugate gradients
  VectorXd F_R_Old;
  VectorXd thetaOld;
  double a{0.0}, b{0.0}, gamma{0.0};
  bool init_cg{false};
 
  // variables for LBFGS
  std::vector<VectorXd> s, y;
  std::vector<double> rho;
  bool init_lbfgs{false};
  VectorXd rPrev;
 
  std::vector<VectorXd> gradients;
  std::vector<VectorXd> positions;
};
 
} // namespace eonc
 
using eonc::ImprovedDimer;