UseTheForce/DarkSide/LJ.F90

!!
!! Copyright (c) 2005 The University of Notre Dame. All Rights Reserved.
!!
!! The University of Notre Dame grants you ("Licensee") a
!! non-exclusive, royalty free, license to use, modify and
!! redistribute this software in source and binary code form, provided
!! that the following conditions are met:
!!
!! 1. Acknowledgement of the program authors must be made in any
!!    publication of scientific results based in part on use of the
!!    program.  An acceptable form of acknowledgement is citation of
!!    the article in which the program was described (Matthew
!!    A. Meineke, Charles F. Vardeman II, Teng Lin, Christopher
!!    J. Fennell and J. Daniel Gezelter, "OOPSE: An Object-Oriented
!!    Parallel Simulation Engine for Molecular Dynamics,"
!!    J. Comput. Chem. 26, pp. 252-271 (2005))
!!
!! 2. Redistributions of source code must retain the above copyright
!!    notice, this list of conditions and the following disclaimer.
!!
!! 3. Redistributions in binary form must reproduce the above copyright
!!    notice, this list of conditions and the following disclaimer in the
!!    documentation and/or other materials provided with the
!!    distribution.
!!
!! This software is provided "AS IS," without a warranty of any
!! kind. All express or implied conditions, representations and
!! warranties, including any implied warranty of merchantability,
!! fitness for a particular purpose or non-infringement, are hereby
!! excluded.  The University of Notre Dame and its licensors shall not
!! be liable for any damages suffered by licensee as a result of
!! using, modifying or distributing the software or its
!! derivatives. In no event will the University of Notre Dame or its
!! licensors be liable for any lost revenue, profit or data, or for
!! direct, indirect, special, consequential, incidental or punitive
!! damages, however caused and regardless of the theory of liability,
!! arising out of the use of or inability to use software, even if the
!! University of Notre Dame has been advised of the possibility of
!! such damages.
!!


!! Calculates Long Range forces Lennard-Jones interactions.
!! @author Charles F. Vardeman II
!! @author Matthew Meineke
!! @version $Id: LJ.F90,v 1.15 2005-09-21 17:20:14 chrisfen Exp $, $Date: 2005-09-21 17:20:14 $, $Name: not supported by cvs2svn $, $Revision: 1.15 $


module lj
  use atype_module
  use vector_class
  use simulation
  use status
#ifdef IS_MPI
  use mpiSimulation
#endif
  use force_globals

  implicit none
  PRIVATE

  integer, parameter :: DP = selected_real_kind(15)

  logical, save :: useGeometricDistanceMixing = .false.
  logical, save :: haveMixingMap = .false.

  real(kind=DP), save :: defaultCutoff = 0.0_DP
  logical, save :: defaultShift = .false.
  logical, save :: haveDefaultCutoff = .false.


  type, private :: LJtype
     integer       :: atid
     real(kind=dp) :: sigma
     real(kind=dp) :: epsilon
     logical       :: isSoftCore = .false.
  end type LJtype

  type, private :: LJList
     integer               :: nLJtypes = 0
     integer               :: currentLJtype = 0
     type(LJtype), pointer :: LJtypes(:)      => null()
     integer, pointer      :: atidToLJtype(:) => null()
  end type LJList

  type(LJList), save :: LJMap

  type :: MixParameters
     real(kind=DP) :: sigma
     real(kind=DP) :: epsilon
     real(kind=dp) :: sigma6
     real(kind=dp) :: rCut
     real(kind=dp) :: delta
     logical       :: rCutWasSet = .false.
     logical       :: shiftedPot
     logical       :: isSoftCore = .false.
  end type MixParameters

  type(MixParameters), dimension(:,:), allocatable :: MixingMap

  public :: newLJtype
  public :: setLJDefaultCutoff
  public :: setLJUniformCutoff
  public :: setLJCutoffByTypes
  public :: getSigma
  public :: getEpsilon
  public :: useGeometricMixing
  public :: do_lj_pair
  public :: destroyLJtypes

contains

  subroutine newLJtype(c_ident, sigma, epsilon, isSoftCore, status)
    integer,intent(in) :: c_ident
    real(kind=dp),intent(in) :: sigma
    real(kind=dp),intent(in) :: epsilon
    integer, intent(in) :: isSoftCore
    integer,intent(out) :: status
    integer :: nLJTypes, ntypes, myATID
    integer, pointer :: MatchList(:) => null()
    integer :: current

    status = 0
    ! check to see if this is the first time into this routine...
    if (.not.associated(LJMap%LJtypes)) then

       call getMatchingElementList(atypes, "is_LennardJones", .true., &
            nLJTypes, MatchList)
       
       LJMap%nLJtypes =  nLJTypes

       allocate(LJMap%LJtypes(nLJTypes))

       ntypes = getSize(atypes)

       allocate(LJMap%atidToLJtype(ntypes))
    end if

    LJMap%currentLJtype = LJMap%currentLJtype + 1
    current = LJMap%currentLJtype

    myATID = getFirstMatchingElement(atypes, "c_ident", c_ident)
    LJMap%atidToLJtype(myATID)        = current
    LJMap%LJtypes(current)%atid       = myATID
    LJMap%LJtypes(current)%sigma      = sigma
    LJMap%LJtypes(current)%epsilon    = epsilon 
    if (isSoftCore .eq. 1) then
       LJMap%LJtypes(current)%isSoftCore = .true.
    else
       LJMap%LJtypes(current)%isSoftCore = .false.
    endif
  end subroutine newLJtype

  subroutine setLJDefaultCutoff(thisRcut, shiftedPot)
    real(kind=dp), intent(in) :: thisRcut
    logical, intent(in) :: shiftedPot
    defaultCutoff = thisRcut
    defaultShift = shiftedPot
    haveDefaultCutoff = .true.
    call createMixingMap()
  end subroutine setLJDefaultCutoff

  subroutine setLJUniformCutoff(thisRcut, shiftedPot)
    real(kind=dp), intent(in) :: thisRcut
    logical, intent(in) :: shiftedPot
    integer :: nLJtypes, i, j

    if (LJMap%currentLJtype == 0) then
       call handleError("LJ", "No members in LJMap")
       return
    end if

    nLJtypes = LJMap%nLJtypes
    if (.not. allocated(MixingMap)) then
       allocate(MixingMap(nLJtypes, nLJtypes))
    endif

    do i = 1, nLJtypes
       do j = 1, nLJtypes
          MixingMap(i,j)%rCut = thisRcut
          MixingMap(i,j)%shiftedPot = shiftedPot
          MixingMap(i,j)%rCutWasSet = .true.
       enddo
    enddo
    call createMixingMap()
  end subroutine setLJUniformCutoff

  subroutine setLJCutoffByTypes(atid1, atid2, thisRcut, shiftedPot)
    integer, intent(in) :: atid1, atid2
    real(kind=dp), intent(in) :: thisRcut
    logical, intent(in) :: shiftedPot
    integer :: nLJtypes, ljt1, ljt2

    if (LJMap%currentLJtype == 0) then
       call handleError("LJ", "No members in LJMap")
       return
    end if

    nLJtypes = LJMap%nLJtypes
    if (.not. allocated(MixingMap)) then
       allocate(MixingMap(nLJtypes, nLJtypes))
    endif

    ljt1 = LJMap%atidToLJtype(atid1)
    ljt2 = LJMap%atidToLJtype(atid2)

    MixingMap(ljt1,ljt2)%rCut = thisRcut
    MixingMap(ljt1,ljt2)%shiftedPot = shiftedPot
    MixingMap(ljt1,ljt2)%rCutWasSet = .true.
    MixingMap(ljt2,ljt1)%rCut = thisRcut
    MixingMap(ljt2,ljt1)%shiftedPot = shiftedPot
    MixingMap(ljt2,ljt1)%rCutWasSet = .true.

    call createMixingMap()
  end subroutine setLJCutoffByTypes

  function getSigma(atid) result (s)
    integer, intent(in) :: atid
    integer :: ljt1
    real(kind=dp) :: s

    if (LJMap%currentLJtype == 0) then
       call handleError("LJ", "No members in LJMap")
       return
    end if

    ljt1 = LJMap%atidToLJtype(atid)
    s = LJMap%LJtypes(ljt1)%sigma

  end function getSigma

  function getEpsilon(atid) result (e)
    integer, intent(in) :: atid
    integer :: ljt1
    real(kind=dp) :: e

    if (LJMap%currentLJtype == 0) then
       call handleError("LJ", "No members in LJMap")
       return
    end if

    ljt1 = LJMap%atidToLJtype(atid)
    e = LJMap%LJtypes(ljt1)%epsilon

  end function getEpsilon

  subroutine useGeometricMixing() 
    useGeometricDistanceMixing = .true.
    haveMixingMap = .false.
    return
  end subroutine useGeometricMixing

  subroutine createMixingMap()
    integer :: nLJtypes, i, j
    real ( kind = dp ) :: s1, s2, e1, e2
    real ( kind = dp ) :: rcut6, tp6, tp12
    logical :: isSoftCore1, isSoftCore2, doShift

    if (LJMap%currentLJtype == 0) then
       call handleError("LJ", "No members in LJMap")
       return
    end if

    nLJtypes = LJMap%nLJtypes

    if (.not. allocated(MixingMap)) then
       allocate(MixingMap(nLJtypes, nLJtypes))
    endif

    do i = 1, nLJtypes

       s1 = LJMap%LJtypes(i)%sigma
       e1 = LJMap%LJtypes(i)%epsilon
       isSoftCore1 = LJMap%LJtypes(i)%isSoftCore

       do j = i, nLJtypes
          
          s2 = LJMap%LJtypes(j)%sigma
          e2 = LJMap%LJtypes(j)%epsilon
          isSoftCore2 = LJMap%LJtypes(j)%isSoftCore
          
          MixingMap(i,j)%isSoftCore = isSoftCore1 .or. isSoftCore2

          ! only the distance parameter uses different mixing policies
          if (useGeometricDistanceMixing) then
             MixingMap(i,j)%sigma = dsqrt(s1 * s2)
          else
             MixingMap(i,j)%sigma = 0.5_dp * (s1 + s2)
          endif
          
          MixingMap(i,j)%epsilon = dsqrt(e1 * e2)

          MixingMap(i,j)%sigma6 = (MixingMap(i,j)%sigma)**6

          if (MixingMap(i,j)%rCutWasSet) then
             rcut6 = (MixingMap(i,j)%rcut)**6
          else
             if (haveDefaultCutoff) then
                rcut6 = defaultCutoff**6
                doShift = defaultShift
             else
                call handleError("LJ", "No specified or default cutoff value!")
             endif
          endif
          
          tp6    = MixingMap(i,j)%sigma6/rcut6
          tp12    = tp6**2          
          MixingMap(i,j)%delta =-4.0_DP*MixingMap(i,j)%epsilon*(tp12 - tp6)
          MixingMap(i,j)%shiftedPot = doShift

          if (i.ne.j) then
             MixingMap(j,i)%sigma      = MixingMap(i,j)%sigma
             MixingMap(j,i)%epsilon    = MixingMap(i,j)%epsilon
             MixingMap(j,i)%sigma6     = MixingMap(i,j)%sigma6
             MixingMap(j,i)%rCut       = MixingMap(i,j)%rCut
             MixingMap(j,i)%delta      = MixingMap(i,j)%delta
             MixingMap(j,i)%rCutWasSet = MixingMap(i,j)%rCutWasSet
             MixingMap(j,i)%shiftedPot = MixingMap(i,j)%shiftedPot
             MixingMap(j,i)%isSoftCore = MixingMap(i,j)%isSoftCore
          endif

       enddo
    enddo
    
    haveMixingMap = .true.
    
  end subroutine createMixingMap
  
  subroutine do_lj_pair(atom1, atom2, d, rij, r2, sw, vpair, fpair, &
       pot, f, do_pot)

    integer, intent(in) ::  atom1, atom2
    integer :: atid1, atid2, ljt1, ljt2
    real( kind = dp ), intent(in) :: rij, r2
    real( kind = dp ) :: pot, sw, vpair
    real( kind = dp ), dimension(3,nLocal) :: f    
    real( kind = dp ), intent(in), dimension(3) :: d
    real( kind = dp ), intent(inout), dimension(3) :: fpair
    logical, intent(in) :: do_pot

    ! local Variables
    real( kind = dp ) :: drdx, drdy, drdz
    real( kind = dp ) :: fx, fy, fz
    real( kind = dp ) :: pot_temp, dudr
    real( kind = dp ) :: sigma6
    real( kind = dp ) :: epsilon
    real( kind = dp ) :: r6
    real( kind = dp ) :: t6
    real( kind = dp ) :: t12
    real( kind = dp ) :: delta
    logical :: isSoftCore, shiftedPot
    integer :: id1, id2, localError

    if (.not.haveMixingMap) then
       call createMixingMap()
    endif

    ! Look up the correct parameters in the mixing matrix
#ifdef IS_MPI
    atid1 = atid_Row(atom1)
    atid2 = atid_Col(atom2)
#else
    atid1 = atid(atom1)
    atid2 = atid(atom2)
#endif

    ljt1 = LJMap%atidToLJtype(atid1)
    ljt2 = LJMap%atidToLJtype(atid2)

    sigma6     = MixingMap(ljt1,ljt2)%sigma6
    epsilon    = MixingMap(ljt1,ljt2)%epsilon
    delta      = MixingMap(ljt1,ljt2)%delta
    isSoftCore = MixingMap(ljt1,ljt2)%isSoftCore
    shiftedPot = MixingMap(ljt1,ljt2)%shiftedPot

    r6 = r2 * r2 * r2

    t6  = sigma6/ r6
    t12 = t6 * t6     

    if (isSoftCore) then
       
       pot_temp = 4.0E0_DP * epsilon * t6
       if (shiftedPot) then
          pot_temp = pot_temp + delta
       endif
       
       vpair = vpair + pot_temp
       
       dudr = -sw * 24.0E0_DP * epsilon * t6 / rij
       
    else
       pot_temp = 4.0E0_DP * epsilon * (t12 - t6) 
       if (shiftedPot) then
          pot_temp = pot_temp + delta
       endif
       
       vpair = vpair + pot_temp
       
       dudr = sw * 24.0E0_DP * epsilon * (t6 - 2.0E0_DP*t12) / rij
    endif

    drdx = d(1) / rij
    drdy = d(2) / rij
    drdz = d(3) / rij

    fx = dudr * drdx
    fy = dudr * drdy
    fz = dudr * drdz

#ifdef IS_MPI
    if (do_pot) then
       pot_Row(atom1) = pot_Row(atom1) + sw*pot_temp*0.5
       pot_Col(atom2) = pot_Col(atom2) + sw*pot_temp*0.5
    endif

    f_Row(1,atom1) = f_Row(1,atom1) + fx 
    f_Row(2,atom1) = f_Row(2,atom1) + fy
    f_Row(3,atom1) = f_Row(3,atom1) + fz

    f_Col(1,atom2) = f_Col(1,atom2) - fx 
    f_Col(2,atom2) = f_Col(2,atom2) - fy
    f_Col(3,atom2) = f_Col(3,atom2) - fz       

#else
    if (do_pot) pot = pot + sw*pot_temp

    f(1,atom1) = f(1,atom1) + fx
    f(2,atom1) = f(2,atom1) + fy
    f(3,atom1) = f(3,atom1) + fz

    f(1,atom2) = f(1,atom2) - fx
    f(2,atom2) = f(2,atom2) - fy
    f(3,atom2) = f(3,atom2) - fz
#endif

#ifdef IS_MPI
    id1 = AtomRowToGlobal(atom1)
    id2 = AtomColToGlobal(atom2)
#else
    id1 = atom1
    id2 = atom2
#endif

    if (molMembershipList(id1) .ne. molMembershipList(id2)) then

       fpair(1) = fpair(1) + fx
       fpair(2) = fpair(2) + fy
       fpair(3) = fpair(3) + fz

    endif

    return    

  end subroutine do_lj_pair

  subroutine destroyLJTypes()

    LJMap%nLJtypes = 0
    LJMap%currentLJtype = 0
    
    if (associated(LJMap%LJtypes)) then
       deallocate(LJMap%LJtypes)
       LJMap%LJtypes => null()
    end if
    
    if (associated(LJMap%atidToLJtype)) then
       deallocate(LJMap%atidToLJtype)
       LJMap%atidToLJtype => null()
    end if
    
    haveMixingMap = .false.
  end subroutine destroyLJTypes

end module lj
Revision:	618
Committed:	Wed Sep 21 17:20:14 2005 UTC (19 years, 10 months ago) by chrisfen
File size:	13871 byte(s)
Log Message:	Fixed a defaultCutoff bug (HEMES!)
#	User	Rev	Content
1	gezelter	246	!!
2			!! Copyright (c) 2005 The University of Notre Dame. All Rights Reserved.
3			!!
4			!! The University of Notre Dame grants you ("Licensee") a
5			!! non-exclusive, royalty free, license to use, modify and
6			!! redistribute this software in source and binary code form, provided
7			!! that the following conditions are met:
8			!!
9			!! 1. Acknowledgement of the program authors must be made in any
10			!! publication of scientific results based in part on use of the
11			!! program. An acceptable form of acknowledgement is citation of
12			!! the article in which the program was described (Matthew
13			!! A. Meineke, Charles F. Vardeman II, Teng Lin, Christopher
14			!! J. Fennell and J. Daniel Gezelter, "OOPSE: An Object-Oriented
15			!! Parallel Simulation Engine for Molecular Dynamics,"
16			!! J. Comput. Chem. 26, pp. 252-271 (2005))
17			!!
18			!! 2. Redistributions of source code must retain the above copyright
19			!! notice, this list of conditions and the following disclaimer.
20			!!
21			!! 3. Redistributions in binary form must reproduce the above copyright
22			!! notice, this list of conditions and the following disclaimer in the
23			!! documentation and/or other materials provided with the
24			!! distribution.
25			!!
26			!! This software is provided "AS IS," without a warranty of any
27			!! kind. All express or implied conditions, representations and
28			!! warranties, including any implied warranty of merchantability,
29			!! fitness for a particular purpose or non-infringement, are hereby
30			!! excluded. The University of Notre Dame and its licensors shall not
31			!! be liable for any damages suffered by licensee as a result of
32			!! using, modifying or distributing the software or its
33			!! derivatives. In no event will the University of Notre Dame or its
34			!! licensors be liable for any lost revenue, profit or data, or for
35			!! direct, indirect, special, consequential, incidental or punitive
36			!! damages, however caused and regardless of the theory of liability,
37			!! arising out of the use of or inability to use software, even if the
38			!! University of Notre Dame has been advised of the possibility of
39			!! such damages.
40			!!
41
42
43	gezelter	115	!! Calculates Long Range forces Lennard-Jones interactions.
44			!! @author Charles F. Vardeman II
45			!! @author Matthew Meineke
46	chrisfen	618	!! @version $Id: LJ.F90,v 1.15 2005-09-21 17:20:14 chrisfen Exp $, $Date: 2005-09-21 17:20:14 $, $Name: not supported by cvs2svn $, $Revision: 1.15 $
47	gezelter	115
48	gezelter	246
49	gezelter	115	module lj
50			use atype_module
51			use vector_class
52			use simulation
53	gezelter	135	use status
54	gezelter	115	#ifdef IS_MPI
55			use mpiSimulation
56			#endif
57			use force_globals
58
59			implicit none
60			PRIVATE
61	gezelter	507
62	chuckv	131	integer, parameter :: DP = selected_real_kind(15)
63	gezelter	507
64	gezelter	572	logical, save :: useGeometricDistanceMixing = .false.
65			logical, save :: haveMixingMap = .false.
66
67			real(kind=DP), save :: defaultCutoff = 0.0_DP
68			logical, save :: defaultShift = .false.
69			logical, save :: haveDefaultCutoff = .false.
70
71
72			type, private :: LJtype
73			integer :: atid
74	gezelter	135	real(kind=dp) :: sigma
75			real(kind=dp) :: epsilon
76	gezelter	572	logical :: isSoftCore = .false.
77			end type LJtype
78	gezelter	507
79	gezelter	572	type, private :: LJList
80			integer :: nLJtypes = 0
81			integer :: currentLJtype = 0
82			type(LJtype), pointer :: LJtypes(:) => null()
83			integer, pointer :: atidToLJtype(:) => null()
84			end type LJList
85	gezelter	507
86	gezelter	572	type(LJList), save :: LJMap
87	gezelter	507
88	gezelter	135	type :: MixParameters
89			real(kind=DP) :: sigma
90			real(kind=DP) :: epsilon
91	gezelter	572	real(kind=dp) :: sigma6
92			real(kind=dp) :: rCut
93			real(kind=dp) :: delta
94			logical :: rCutWasSet = .false.
95			logical :: shiftedPot
96			logical :: isSoftCore = .false.
97	gezelter	135	end type MixParameters
98	gezelter	507
99	gezelter	135	type(MixParameters), dimension(:,:), allocatable :: MixingMap
100	gezelter	507
101	gezelter	572	public :: newLJtype
102			public :: setLJDefaultCutoff
103			public :: setLJUniformCutoff
104			public :: setLJCutoffByTypes
105			public :: getSigma
106			public :: getEpsilon
107	gezelter	135	public :: useGeometricMixing
108			public :: do_lj_pair
109	gezelter	572	public :: destroyLJtypes
110	gezelter	507
111	gezelter	115	contains
112
113	gezelter	572	subroutine newLJtype(c_ident, sigma, epsilon, isSoftCore, status)
114	gezelter	246	integer,intent(in) :: c_ident
115	gezelter	135	real(kind=dp),intent(in) :: sigma
116			real(kind=dp),intent(in) :: epsilon
117	gezelter	572	integer, intent(in) :: isSoftCore
118	chuckv	131	integer,intent(out) :: status
119	gezelter	572	integer :: nLJTypes, ntypes, myATID
120	gezelter	246	integer, pointer :: MatchList(:) => null()
121	gezelter	572	integer :: current
122	gezelter	135
123	chuckv	131	status = 0
124	gezelter	572	! check to see if this is the first time into this routine...
125			if (.not.associated(LJMap%LJtypes)) then
126	gezelter	507
127	gezelter	572	call getMatchingElementList(atypes, "is_LennardJones", .true., &
128			nLJTypes, MatchList)
129
130			LJMap%nLJtypes = nLJTypes
131
132			allocate(LJMap%LJtypes(nLJTypes))
133
134			ntypes = getSize(atypes)
135
136			allocate(LJMap%atidToLJtype(ntypes))
137			end if
138
139			LJMap%currentLJtype = LJMap%currentLJtype + 1
140			current = LJMap%currentLJtype
141
142	gezelter	246	myATID = getFirstMatchingElement(atypes, "c_ident", c_ident)
143	gezelter	572	LJMap%atidToLJtype(myATID) = current
144			LJMap%LJtypes(current)%atid = myATID
145			LJMap%LJtypes(current)%sigma = sigma
146			LJMap%LJtypes(current)%epsilon = epsilon
147			if (isSoftCore .eq. 1) then
148			LJMap%LJtypes(current)%isSoftCore = .true.
149			else
150			LJMap%LJtypes(current)%isSoftCore = .false.
151			endif
152			end subroutine newLJtype
153	chuckv	131
154	gezelter	572	subroutine setLJDefaultCutoff(thisRcut, shiftedPot)
155			real(kind=dp), intent(in) :: thisRcut
156			logical, intent(in) :: shiftedPot
157			defaultCutoff = thisRcut
158			defaultShift = shiftedPot
159			haveDefaultCutoff = .true.
160	chrisfen	618	call createMixingMap()
161	gezelter	572	end subroutine setLJDefaultCutoff
162	gezelter	507
163	gezelter	572	subroutine setLJUniformCutoff(thisRcut, shiftedPot)
164			real(kind=dp), intent(in) :: thisRcut
165			logical, intent(in) :: shiftedPot
166			integer :: nLJtypes, i, j
167	gezelter	507
168	gezelter	572	if (LJMap%currentLJtype == 0) then
169			call handleError("LJ", "No members in LJMap")
170			return
171	chuckv	131	end if
172
173	gezelter	572	nLJtypes = LJMap%nLJtypes
174			if (.not. allocated(MixingMap)) then
175			allocate(MixingMap(nLJtypes, nLJtypes))
176	gezelter	135	endif
177	gezelter	507
178	gezelter	572	do i = 1, nLJtypes
179			do j = 1, nLJtypes
180			MixingMap(i,j)%rCut = thisRcut
181			MixingMap(i,j)%shiftedPot = shiftedPot
182			MixingMap(i,j)%rCutWasSet = .true.
183			enddo
184			enddo
185			call createMixingMap()
186			end subroutine setLJUniformCutoff
187	gezelter	135
188	gezelter	572	subroutine setLJCutoffByTypes(atid1, atid2, thisRcut, shiftedPot)
189			integer, intent(in) :: atid1, atid2
190			real(kind=dp), intent(in) :: thisRcut
191			logical, intent(in) :: shiftedPot
192			integer :: nLJtypes, ljt1, ljt2
193
194			if (LJMap%currentLJtype == 0) then
195			call handleError("LJ", "No members in LJMap")
196			return
197			end if
198
199			nLJtypes = LJMap%nLJtypes
200			if (.not. allocated(MixingMap)) then
201			allocate(MixingMap(nLJtypes, nLJtypes))
202	tim	378	endif
203	gezelter	140
204	gezelter	572	ljt1 = LJMap%atidToLJtype(atid1)
205			ljt2 = LJMap%atidToLJtype(atid2)
206
207			MixingMap(ljt1,ljt2)%rCut = thisRcut
208			MixingMap(ljt1,ljt2)%shiftedPot = shiftedPot
209			MixingMap(ljt1,ljt2)%rCutWasSet = .true.
210			MixingMap(ljt2,ljt1)%rCut = thisRcut
211			MixingMap(ljt2,ljt1)%shiftedPot = shiftedPot
212			MixingMap(ljt2,ljt1)%rCutWasSet = .true.
213
214			call createMixingMap()
215			end subroutine setLJCutoffByTypes
216
217	gezelter	140	function getSigma(atid) result (s)
218			integer, intent(in) :: atid
219	gezelter	572	integer :: ljt1
220	gezelter	140	real(kind=dp) :: s
221	gezelter	507
222	gezelter	572	if (LJMap%currentLJtype == 0) then
223			call handleError("LJ", "No members in LJMap")
224	gezelter	140	return
225			end if
226	gezelter	507
227	gezelter	572	ljt1 = LJMap%atidToLJtype(atid)
228			s = LJMap%LJtypes(ljt1)%sigma
229
230	gezelter	140	end function getSigma
231
232			function getEpsilon(atid) result (e)
233			integer, intent(in) :: atid
234	gezelter	572	integer :: ljt1
235	gezelter	140	real(kind=dp) :: e
236	gezelter	507
237	gezelter	572	if (LJMap%currentLJtype == 0) then
238			call handleError("LJ", "No members in LJMap")
239	gezelter	140	return
240			end if
241	gezelter	507
242	gezelter	572	ljt1 = LJMap%atidToLJtype(atid)
243			e = LJMap%LJtypes(ljt1)%epsilon
244
245	gezelter	140	end function getEpsilon
246
247	gezelter	135	subroutine useGeometricMixing()
248			useGeometricDistanceMixing = .true.
249			haveMixingMap = .false.
250			return
251			end subroutine useGeometricMixing
252	gezelter	507
253	gezelter	572	subroutine createMixingMap()
254			integer :: nLJtypes, i, j
255			real ( kind = dp ) :: s1, s2, e1, e2
256			real ( kind = dp ) :: rcut6, tp6, tp12
257	gezelter	590	logical :: isSoftCore1, isSoftCore2, doShift
258	gezelter	135
259	gezelter	572	if (LJMap%currentLJtype == 0) then
260			call handleError("LJ", "No members in LJMap")
261	gezelter	402	return
262	gezelter	572	end if
263	gezelter	507
264	gezelter	572	nLJtypes = LJMap%nLJtypes
265	gezelter	507
266	gezelter	402	if (.not. allocated(MixingMap)) then
267	gezelter	572	allocate(MixingMap(nLJtypes, nLJtypes))
268	gezelter	402	endif
269
270	gezelter	572	do i = 1, nLJtypes
271	gezelter	507
272	gezelter	572	s1 = LJMap%LJtypes(i)%sigma
273			e1 = LJMap%LJtypes(i)%epsilon
274			isSoftCore1 = LJMap%LJtypes(i)%isSoftCore
275	gezelter	507
276	gezelter	572	do j = i, nLJtypes
277
278			s2 = LJMap%LJtypes(j)%sigma
279			e2 = LJMap%LJtypes(j)%epsilon
280			isSoftCore2 = LJMap%LJtypes(j)%isSoftCore
281
282			MixingMap(i,j)%isSoftCore = isSoftCore1 .or. isSoftCore2
283	gezelter	507
284	gezelter	572	! only the distance parameter uses different mixing policies
285			if (useGeometricDistanceMixing) then
286			MixingMap(i,j)%sigma = dsqrt(s1 * s2)
287			else
288			MixingMap(i,j)%sigma = 0.5_dp * (s1 + s2)
289			endif
290
291			MixingMap(i,j)%epsilon = dsqrt(e1 * e2)
292	gezelter	507
293	gezelter	572	MixingMap(i,j)%sigma6 = (MixingMap(i,j)%sigma)**6
294	gezelter	507
295	gezelter	572	if (MixingMap(i,j)%rCutWasSet) then
296			rcut6 = (MixingMap(i,j)%rcut)**6
297			else
298			if (haveDefaultCutoff) then
299			rcut6 = defaultCutoff**6
300	gezelter	590	doShift = defaultShift
301	gezelter	572	else
302			call handleError("LJ", "No specified or default cutoff value!")
303	gezelter	402	endif
304	gezelter	572	endif
305
306			tp6 = MixingMap(i,j)%sigma6/rcut6
307			tp12 = tp6**2
308	gezelter	590	MixingMap(i,j)%delta =-4.0_DPMixingMap(i,j)%epsilon(tp12 - tp6)
309			MixingMap(i,j)%shiftedPot = doShift
310	gezelter	507
311	gezelter	590	if (i.ne.j) then
312			MixingMap(j,i)%sigma = MixingMap(i,j)%sigma
313			MixingMap(j,i)%epsilon = MixingMap(i,j)%epsilon
314			MixingMap(j,i)%sigma6 = MixingMap(i,j)%sigma6
315			MixingMap(j,i)%rCut = MixingMap(i,j)%rCut
316			MixingMap(j,i)%delta = MixingMap(i,j)%delta
317			MixingMap(j,i)%rCutWasSet = MixingMap(i,j)%rCutWasSet
318			MixingMap(j,i)%shiftedPot = MixingMap(i,j)%shiftedPot
319			MixingMap(j,i)%isSoftCore = MixingMap(i,j)%isSoftCore
320			endif
321
322	gezelter	572	enddo
323			enddo
324
325	chrisfen	217	haveMixingMap = .true.
326	gezelter	572
327	gezelter	135	end subroutine createMixingMap
328	gezelter	572
329	gezelter	115	subroutine do_lj_pair(atom1, atom2, d, rij, r2, sw, vpair, fpair, &
330			pot, f, do_pot)
331
332			integer, intent(in) :: atom1, atom2
333	gezelter	572	integer :: atid1, atid2, ljt1, ljt2
334	gezelter	115	real( kind = dp ), intent(in) :: rij, r2
335			real( kind = dp ) :: pot, sw, vpair
336			real( kind = dp ), dimension(3,nLocal) :: f
337			real( kind = dp ), intent(in), dimension(3) :: d
338			real( kind = dp ), intent(inout), dimension(3) :: fpair
339			logical, intent(in) :: do_pot
340
341			! local Variables
342			real( kind = dp ) :: drdx, drdy, drdz
343			real( kind = dp ) :: fx, fy, fz
344			real( kind = dp ) :: pot_temp, dudr
345			real( kind = dp ) :: sigma6
346			real( kind = dp ) :: epsilon
347			real( kind = dp ) :: r6
348			real( kind = dp ) :: t6
349			real( kind = dp ) :: t12
350			real( kind = dp ) :: delta
351	gezelter	572	logical :: isSoftCore, shiftedPot
352	gezelter	135	integer :: id1, id2, localError
353	gezelter	115
354	gezelter	135	if (.not.haveMixingMap) then
355	gezelter	572	call createMixingMap()
356	gezelter	135	endif
357
358	gezelter	115	! Look up the correct parameters in the mixing matrix
359			#ifdef IS_MPI
360	gezelter	572	atid1 = atid_Row(atom1)
361			atid2 = atid_Col(atom2)
362	gezelter	115	#else
363	gezelter	572	atid1 = atid(atom1)
364			atid2 = atid(atom2)
365	gezelter	115	#endif
366
367	gezelter	572	ljt1 = LJMap%atidToLJtype(atid1)
368			ljt2 = LJMap%atidToLJtype(atid2)
369
370			sigma6 = MixingMap(ljt1,ljt2)%sigma6
371			epsilon = MixingMap(ljt1,ljt2)%epsilon
372			delta = MixingMap(ljt1,ljt2)%delta
373			isSoftCore = MixingMap(ljt1,ljt2)%isSoftCore
374			shiftedPot = MixingMap(ljt1,ljt2)%shiftedPot
375
376	gezelter	115	r6 = r2 * r2 * r2
377	gezelter	507
378	gezelter	115	t6 = sigma6/ r6
379			t12 = t6 * t6
380	tim	378
381	gezelter	572	if (isSoftCore) then
382
383			pot_temp = 4.0E0_DP * epsilon * t6
384			if (shiftedPot) then
385			pot_temp = pot_temp + delta
386			endif
387
388			vpair = vpair + pot_temp
389
390			dudr = -sw * 24.0E0_DP * epsilon * t6 / rij
391
392	tim	378	else
393	gezelter	507	pot_temp = 4.0E0_DP * epsilon * (t12 - t6)
394	gezelter	572	if (shiftedPot) then
395	gezelter	507	pot_temp = pot_temp + delta
396			endif
397	gezelter	572
398	gezelter	507	vpair = vpair + pot_temp
399	gezelter	572
400	gezelter	507	dudr = sw * 24.0E0_DP * epsilon * (t6 - 2.0E0_DP*t12) / rij
401	gezelter	115	endif
402	gezelter	507
403	gezelter	115	drdx = d(1) / rij
404			drdy = d(2) / rij
405			drdz = d(3) / rij
406	gezelter	507
407	gezelter	115	fx = dudr * drdx
408			fy = dudr * drdy
409			fz = dudr * drdz
410	gezelter	507
411	gezelter	115	#ifdef IS_MPI
412			if (do_pot) then
413			pot_Row(atom1) = pot_Row(atom1) + swpot_temp0.5
414			pot_Col(atom2) = pot_Col(atom2) + swpot_temp0.5
415			endif
416	gezelter	507
417	gezelter	115	f_Row(1,atom1) = f_Row(1,atom1) + fx
418			f_Row(2,atom1) = f_Row(2,atom1) + fy
419			f_Row(3,atom1) = f_Row(3,atom1) + fz
420	gezelter	507
421	gezelter	115	f_Col(1,atom2) = f_Col(1,atom2) - fx
422			f_Col(2,atom2) = f_Col(2,atom2) - fy
423			f_Col(3,atom2) = f_Col(3,atom2) - fz
424	gezelter	507
425	gezelter	115	#else
426			if (do_pot) pot = pot + sw*pot_temp
427
428			f(1,atom1) = f(1,atom1) + fx
429			f(2,atom1) = f(2,atom1) + fy
430			f(3,atom1) = f(3,atom1) + fz
431	gezelter	507
432	gezelter	115	f(1,atom2) = f(1,atom2) - fx
433			f(2,atom2) = f(2,atom2) - fy
434			f(3,atom2) = f(3,atom2) - fz
435			#endif
436	gezelter	507
437	gezelter	115	#ifdef IS_MPI
438			id1 = AtomRowToGlobal(atom1)
439			id2 = AtomColToGlobal(atom2)
440			#else
441			id1 = atom1
442			id2 = atom2
443			#endif
444
445			if (molMembershipList(id1) .ne. molMembershipList(id2)) then
446	gezelter	507
447	gezelter	115	fpair(1) = fpair(1) + fx
448			fpair(2) = fpair(2) + fy
449			fpair(3) = fpair(3) + fz
450
451			endif
452
453			return
454	gezelter	507
455	gezelter	115	end subroutine do_lj_pair
456	gezelter	507
457	chuckv	492	subroutine destroyLJTypes()
458	gezelter	572
459			LJMap%nLJtypes = 0
460			LJMap%currentLJtype = 0
461
462			if (associated(LJMap%LJtypes)) then
463			deallocate(LJMap%LJtypes)
464			LJMap%LJtypes => null()
465			end if
466
467			if (associated(LJMap%atidToLJtype)) then
468			deallocate(LJMap%atidToLJtype)
469			LJMap%atidToLJtype => null()
470			end if
471
472	chuckv	492	haveMixingMap = .false.
473			end subroutine destroyLJTypes
474
475	gezelter	115	end module lj