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35 #ifndef GMX_MDLIB_DISPERSIONCORRECTION_H
36 #define GMX_MDLIB_DISPERSIONCORRECTION_H
42 #include "gromacs/math/vectypes.h"
43 #include "gromacs/utility/arrayref.h"
46 struct interaction_const_t;
56 class DispersionCorrection
59 /*! \brief Constructor
61 * \param[in] mtop The global topology
62 * \param[in] inputrec The input record
63 * \param[in] useBuckingham True when Buckingham is used instead of LJ
64 * \param[in] numAtomTypes The number of non-bonded atom types
65 * \param[in] nonbondedForceParameters The LJ or Bham parameter matrix stored as a flat list
66 * \param[in] ic The nonbonded interaction parameters
67 * \param[in] tableFileName Table file name, should != nullptr (checked)
69 DispersionCorrection(const gmx_mtop_t& mtop,
70 const t_inputrec& inputrec,
73 gmx::ArrayRef<const real> nonbondedForceParameters,
74 const interaction_const_t& ic,
75 const char* tableFileName);
77 /*! \brief Print dispersion correction information to the log file
79 * \param[in] mdlog The MD logger
81 void print(const gmx::MDLogger& mdlog) const;
83 /*! \brief Computes and sets energy and virial correction parameters
85 * Sets all parameters that are affected by the cut-off and/or the
86 * LJ-Ewald coefficient. Should be called before calling calculate()
87 * and whenever interaction settings change, e.g. PME tuning.
89 * \param[in] ic The nonbonded interaction parameters
91 void setParameters(const interaction_const_t& ic);
94 * \brief Struct for returning all dispersion correction quantities
98 /*! \brief Correct the virial tensor for the missing dispersion
100 * \param[in,out] virialTensor The virial tensor to correct
102 void correctVirial(tensor virialTensor) const
104 for (int m = 0; m < DIM; m++)
106 virialTensor[m][m] += virial;
110 /*! \brief Correct the pressure tensor for the missing dispersion
112 * \param[in,out] pressureTensor The pressure tensor to correct
114 void correctPressure(tensor pressureTensor) const
116 for (int m = 0; m < DIM; m++)
118 pressureTensor[m][m] += pressure;
122 real virial = 0; //!< Scalar correction to the virial
123 real pressure = 0; //!< Scalar correction to the pressure
124 real energy = 0; //!< Correction to the energy
125 real dvdl = 0; //!< Correction to dH/dlambda
128 /*! \brief Computes and returns the dispersion correction for the pressure and energy
130 * \param[in] box The simulation unit cell
131 * \param[in] lambda The free-energy coupling parameter
133 Correction calculate(const matrix box, real lambda) const;
136 /*! \internal \brief Parameters that depend on the topology only
141 TopologyParams(const gmx_mtop_t& mtop,
142 const t_inputrec& inputrec,
145 gmx::ArrayRef<const real> nonbondedForceParameters);
147 //! The number of atoms for computing the atom density
148 int numAtomsForDensity_;
149 //! The number of interactions to correct for, usually num. atoms/2
150 real numCorrections_;
151 //! Average C6 coefficient for for topology A/B ([0]/[1])
152 std::array<real, 2> avcsix_;
153 //! Average C12 coefficient for for topology A/B ([0]/[1])
154 std::array<real, 2> avctwelve_;
157 /*! \internal \brief Parameters that depend on the interaction functions and topology
159 struct InteractionParams
162 ~InteractionParams();
164 //! Table used for correcting modified LJ interactions
165 std::unique_ptr<t_forcetable> dispersionCorrectionTable_;
167 //! Dispersion energy shift constant
168 real enershiftsix_ = 0;
169 //! Repulsion energy shift constant
170 real enershifttwelve_ = 0;
171 //! Dispersion energy difference per atom per unit of volume
172 real enerdiffsix_ = 0;
173 //! Repulsion energy difference per atom per unit of volume
174 real enerdifftwelve_ = 0;
175 //! Dispersion virial difference per atom per unit of volume
176 real virdiffsix_ = 0;
177 //! Repulsion virial difference per atom per unit of volume
178 real virdifftwelve_ = 0;
181 //! Sets the interaction parameters
182 static void setInteractionParameters(DispersionCorrection::InteractionParams* iParams,
183 const interaction_const_t& ic,
184 const char* tableFileName);
186 //! Returns whether we correct both dispersion and repulsion
187 bool correctFullInteraction() const;
189 //! Type of dispersion correction
191 //! Type of Van der Waals interaction
193 //! Free-energy perturbation
195 //! Topology parameters
196 TopologyParams topParams_;
197 //! Interaction parameters
198 InteractionParams iParams_;