1 |
!! Calculates Long Range forces Lennard-Jones interactions. |
2 |
!! Corresponds to the force field defined in lj_FF.cpp |
3 |
!! @author Charles F. Vardeman II |
4 |
!! @author Matthew Meineke |
5 |
!! @version $Id: lj_FF.F90,v 1.1 2003-02-14 17:08:45 mmeineke Exp $, $Date: 2003-02-14 17:08:45 $, $Name: not supported by cvs2svn $, $Revision: 1.1 $ |
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module lj_ff |
10 |
use simulation |
11 |
use definitions |
12 |
use generic_atypes |
13 |
#ifdef IS_MPI |
14 |
use mpiSimulation |
15 |
#endif |
16 |
implicit none |
17 |
PRIVATE |
18 |
|
19 |
!! Number of lj_atypes in lj_atype_list |
20 |
integer, save :: n_lj_atypes = 0 |
21 |
|
22 |
!! Global list of lj atypes in simulation |
23 |
type (lj_atype), pointer :: ljListHead => null() |
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type (lj_atype), pointer :: ljListTail => null() |
25 |
|
26 |
|
27 |
!! LJ mixing array |
28 |
type (lj_atype), dimension(:,:), pointer :: ljMixed => null() |
29 |
|
30 |
|
31 |
!! Neighbor list and commom arrays |
32 |
!! This should eventally get moved to a neighbor list type |
33 |
integer, allocatable, dimension(:) :: point |
34 |
integer, allocatable, dimension(:) :: list |
35 |
integer, parameter :: listMultiplier = 80 |
36 |
integer :: nListAllocs = 0 |
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integer, parameter :: maxListAllocs = 5 |
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|
39 |
logical, save :: firstTime = .True. |
40 |
|
41 |
!! Atype identity pointer lists |
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#ifdef IS_MPI |
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!! Row lj_atype pointer list |
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type (lj_identPtrList), dimension(:), pointer :: identPtrListRow => null() |
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!! Column lj_atype pointer list |
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type (lj_identPtrList), dimension(:), pointer :: identPtrListColumn => null() |
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#else |
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type( lj_identPtrList ), dimension(:), pointer :: identPtrList => null() |
49 |
#endif |
50 |
|
51 |
|
52 |
!! Logical has lj force field module been initialized? |
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logical, save :: isljFFinit = .false. |
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|
55 |
|
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!! Public methods and data |
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public :: new_lj_atype |
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public :: do_lj_ff |
59 |
public :: getLjPot |
60 |
public :: init_ljFF |
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|
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|
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|
64 |
|
65 |
contains |
66 |
|
67 |
!! Adds a new lj_atype to the list. |
68 |
subroutine new_lj_atype(ident,mass,epsilon,sigma,status) |
69 |
real( kind = dp ), intent(in) :: mass |
70 |
real( kind = dp ), intent(in) :: epsilon |
71 |
real( kind = dp ), intent(in) :: sigma |
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integer, intent(in) :: ident |
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integer, intent(out) :: status |
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|
75 |
type (lj_atype), pointer :: newLJ_atype |
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integer :: alloc_error |
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integer :: atype_counter = 0 |
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integer :: alloc_size |
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integer :: err_stat |
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status = 0 |
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|
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|
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|
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! allocate a new atype |
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allocate(newLJ_atype,stat=alloc_error) |
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if (alloc_error /= 0 ) then |
87 |
status = -1 |
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return |
89 |
end if |
90 |
|
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! assign our new lj_atype information |
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newLJ_atype%mass = mass |
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newLJ_atype%epsilon = epsilon |
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newLJ_atype%sigma = sigma |
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newLJ_atype%sigma2 = sigma * sigma |
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newLJ_atype%sigma6 = newLJ_atype%sigma2 * newLJ_atype%sigma2 & |
97 |
* newLJ_atype%sigma2 |
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! assume that this atype will be successfully added |
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newLJ_atype%atype_ident = ident |
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newLJ_atype%atype_number = n_lj_atypes + 1 |
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|
102 |
call add_atype(newLJ_atype,ljListHead,ljListTail,err_stat) |
103 |
if (err_stat /= 0 ) then |
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status = -1 |
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return |
106 |
endif |
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|
108 |
n_lj_atypes = n_lj_atypes + 1 |
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|
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|
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end subroutine new_lj_atype |
112 |
|
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|
114 |
subroutine init_ljFF(nComponents,ident, status) |
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!! Number of components in ident array |
116 |
integer, intent(inout) :: nComponents |
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!! Array of identities nComponents long corresponding to |
118 |
!! ljatype ident. |
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integer, dimension(nComponents),intent(inout) :: ident |
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!! Result status, success = 0, error = -1 |
121 |
integer, intent(out) :: Status |
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|
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integer :: alloc_stat |
124 |
|
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integer :: thisStat |
126 |
integer :: i |
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|
128 |
integer :: myNode |
129 |
#ifdef IS_MPI |
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integer, allocatable, dimension(:) :: identRow |
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integer, allocatable, dimension(:) :: identCol |
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integer :: nrow |
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integer :: ncol |
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#endif |
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status = 0 |
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|
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|
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|
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|
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!! if were're not in MPI, we just update ljatypePtrList |
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#ifndef IS_MPI |
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call create_IdentPtrlst(ident,ljListHead,identPtrList,thisStat) |
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if ( thisStat /= 0 ) then |
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status = -1 |
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return |
146 |
endif |
147 |
|
148 |
!! Allocate pointer lists |
149 |
allocate(point(nComponents),stat=alloc_stat) |
150 |
if (alloc_stat /=0) then |
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status = -1 |
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return |
153 |
endif |
154 |
|
155 |
allocate(list(nComponents*listMultiplier),stat=alloc_stat) |
156 |
if (alloc_stat /=0) then |
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status = -1 |
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return |
159 |
endif |
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|
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! if were're in MPI, we also have to worry about row and col lists |
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#else |
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|
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! We can only set up forces if mpiSimulation has been setup. |
165 |
if (.not. isMPISimSet()) then |
166 |
write(default_error,*) "MPI is not set" |
167 |
status = -1 |
168 |
return |
169 |
endif |
170 |
nrow = getNrow(plan_row) |
171 |
ncol = getNcol(plan_col) |
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mynode = getMyNode() |
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!! Allocate temperary arrays to hold gather information |
174 |
allocate(identRow(nrow),stat=alloc_stat) |
175 |
if (alloc_stat /= 0 ) then |
176 |
status = -1 |
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return |
178 |
endif |
179 |
|
180 |
allocate(identCol(ncol),stat=alloc_stat) |
181 |
if (alloc_stat /= 0 ) then |
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status = -1 |
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return |
184 |
endif |
185 |
|
186 |
!! Gather idents into row and column idents |
187 |
|
188 |
call gather(ident,identRow,plan_row) |
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call gather(ident,identCol,plan_col) |
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|
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|
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!! Create row and col pointer lists |
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|
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call create_IdentPtrlst(identRow,ljListHead,identPtrListRow,thisStat) |
195 |
if (thisStat /= 0 ) then |
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status = -1 |
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return |
198 |
endif |
199 |
|
200 |
call create_IdentPtrlst(identCol,ljListHead,identPtrListColumn,thisStat) |
201 |
if (thisStat /= 0 ) then |
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status = -1 |
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return |
204 |
endif |
205 |
|
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!! free temporary ident arrays |
207 |
if (allocated(identCol)) then |
208 |
deallocate(identCol) |
209 |
end if |
210 |
if (allocated(identCol)) then |
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deallocate(identRow) |
212 |
endif |
213 |
|
214 |
!! Allocate neighbor lists for mpi simulations. |
215 |
if (.not. allocated(point)) then |
216 |
allocate(point(nrow),stat=alloc_stat) |
217 |
if (alloc_stat /=0) then |
218 |
status = -1 |
219 |
return |
220 |
endif |
221 |
|
222 |
allocate(list(ncol*listMultiplier),stat=alloc_stat) |
223 |
if (alloc_stat /=0) then |
224 |
status = -1 |
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return |
226 |
endif |
227 |
else |
228 |
deallocate(list) |
229 |
deallocate(point) |
230 |
allocate(point(nrow),stat=alloc_stat) |
231 |
if (alloc_stat /=0) then |
232 |
status = -1 |
233 |
return |
234 |
endif |
235 |
|
236 |
allocate(list(ncol*listMultiplier),stat=alloc_stat) |
237 |
if (alloc_stat /=0) then |
238 |
status = -1 |
239 |
return |
240 |
endif |
241 |
endif |
242 |
|
243 |
#endif |
244 |
|
245 |
call createMixingList(thisStat) |
246 |
if (thisStat /= 0) then |
247 |
status = -1 |
248 |
return |
249 |
endif |
250 |
isljFFinit = .true. |
251 |
|
252 |
|
253 |
end subroutine init_ljFF |
254 |
|
255 |
|
256 |
|
257 |
|
258 |
|
259 |
|
260 |
subroutine createMixingList(status) |
261 |
integer :: listSize |
262 |
integer :: status |
263 |
integer :: i |
264 |
integer :: j |
265 |
|
266 |
integer :: outerCounter = 0 |
267 |
integer :: innerCounter = 0 |
268 |
type (lj_atype), pointer :: tmpPtrOuter => null() |
269 |
type (lj_atype), pointer :: tmpPtrInner => null() |
270 |
status = 0 |
271 |
|
272 |
listSize = getListLen(ljListHead) |
273 |
if (listSize == 0) then |
274 |
status = -1 |
275 |
return |
276 |
end if |
277 |
|
278 |
|
279 |
if (.not. associated(ljMixed)) then |
280 |
allocate(ljMixed(listSize,listSize)) |
281 |
else |
282 |
status = -1 |
283 |
return |
284 |
end if |
285 |
|
286 |
|
287 |
|
288 |
tmpPtrOuter => ljListHead |
289 |
tmpPtrInner => tmpPtrOuter%next |
290 |
do while (associated(tmpPtrOuter)) |
291 |
outerCounter = outerCounter + 1 |
292 |
! do self mixing rule |
293 |
ljMixed(outerCounter,outerCounter)%sigma = tmpPtrOuter%sigma |
294 |
|
295 |
ljMixed(outerCounter,outerCounter)%sigma2 = ljMixed(outerCounter,outerCounter)%sigma & |
296 |
* ljMixed(outerCounter,outerCounter)%sigma |
297 |
|
298 |
ljMixed(outerCounter,outerCounter)%sigma6 = ljMixed(outerCounter,outerCounter)%sigma2 & |
299 |
* ljMixed(outerCounter,outerCounter)%sigma2 & |
300 |
* ljMixed(outerCounter,outerCounter)%sigma2 |
301 |
|
302 |
ljMixed(outerCounter,outerCounter)%epsilon = tmpPtrOuter%epsilon |
303 |
|
304 |
innerCounter = outerCounter + 1 |
305 |
do while (associated(tmpPtrInner)) |
306 |
|
307 |
ljMixed(outerCounter,innerCounter)%sigma = & |
308 |
calcLJMix("sigma",tmpPtrOuter%sigma, & |
309 |
tmpPtrInner%sigma) |
310 |
|
311 |
ljMixed(outerCounter,innerCounter)%sigma2 = & |
312 |
ljMixed(outerCounter,innerCounter)%sigma & |
313 |
* ljMixed(outerCounter,innerCounter)%sigma |
314 |
|
315 |
ljMixed(outerCounter,innerCounter)%sigma6 = & |
316 |
ljMixed(outerCounter,innerCounter)%sigma2 & |
317 |
* ljMixed(outerCounter,innerCounter)%sigma2 & |
318 |
* ljMixed(outerCounter,innerCounter)%sigma2 |
319 |
|
320 |
ljMixed(outerCounter,innerCounter)%epsilon = & |
321 |
calcLJMix("epsilon",tmpPtrOuter%epsilon, & |
322 |
tmpPtrInner%epsilon) |
323 |
ljMixed(innerCounter,outerCounter)%sigma = ljMixed(outerCounter,innerCounter)%sigma |
324 |
ljMixed(innerCounter,outerCounter)%sigma2 = ljMixed(outerCounter,innerCounter)%sigma2 |
325 |
ljMixed(innerCounter,outerCounter)%sigma6 = ljMixed(outerCounter,innerCounter)%sigma6 |
326 |
ljMixed(innerCounter,outerCounter)%epsilon = ljMixed(outerCounter,innerCounter)%epsilon |
327 |
|
328 |
|
329 |
tmpPtrInner => tmpPtrInner%next |
330 |
innerCounter = innerCounter + 1 |
331 |
end do |
332 |
! advance pointers |
333 |
tmpPtrOuter => tmpPtrOuter%next |
334 |
if (associated(tmpPtrOuter)) then |
335 |
tmpPtrInner => tmpPtrOuter%next |
336 |
endif |
337 |
|
338 |
end do |
339 |
|
340 |
end subroutine createMixingList |
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|
342 |
|
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|
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|
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|
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|
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|
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|
349 |
!! FORCE routine Calculates Lennard Jones forces. |
350 |
!-------------------------------------------------------------> |
351 |
subroutine do_lj_ff(q,f,potE,do_pot) |
352 |
!! Position array provided by C, dimensioned by getNlocal |
353 |
real ( kind = dp ), dimension(3,getNlocal()) :: q |
354 |
!! Force array provided by C, dimensioned by getNlocal |
355 |
real ( kind = dp ), dimension(3,getNlocal()) :: f |
356 |
real ( kind = dp ) :: potE |
357 |
logical ( kind = 2) :: do_pot |
358 |
|
359 |
type(lj_atype), pointer :: ljAtype_i |
360 |
type(lj_atype), pointer :: ljAtype_j |
361 |
|
362 |
#ifdef IS_MPI |
363 |
real( kind = DP ), dimension(3,getNcol(plan_col)) :: efr |
364 |
real( kind = DP ) :: pot_local |
365 |
#else |
366 |
real( kind = DP ), dimension(3,getNlocal()) :: efr |
367 |
#endif |
368 |
|
369 |
!! Local arrays needed for MPI |
370 |
#ifdef IS_MPI |
371 |
real(kind = dp), dimension(3,getNrow(plan_row)) :: qRow |
372 |
real(kind = dp), dimension(3,getNcol(plan_col)) :: qCol |
373 |
|
374 |
real(kind = dp), dimension(3,getNrow(plan_row)) :: fRow |
375 |
real(kind = dp), dimension(3,getNcol(plan_col)) :: fCol |
376 |
real(kind = dp), dimension(3,getNlocal()) :: fMPITemp |
377 |
|
378 |
real(kind = dp), dimension(getNrow(plan_row)) :: eRow |
379 |
real(kind = dp), dimension(getNcol(plan_col)) :: eCol |
380 |
|
381 |
real(kind = dp), dimension(getNlocal()) :: eTemp |
382 |
#endif |
383 |
|
384 |
|
385 |
|
386 |
real( kind = DP ) :: pe |
387 |
logical :: update_nlist |
388 |
|
389 |
|
390 |
integer :: i, j, jbeg, jend, jnab, idim, jdim, idim2, jdim2, dim, dim2 |
391 |
integer :: nlist |
392 |
integer :: j_start |
393 |
integer :: tag_i,tag_j |
394 |
real( kind = DP ) :: r, pot, ftmp, dudr, d2, drdx1, kt1, kt2, kt3, ktmp |
395 |
real( kind = DP ) :: rxi, ryi, rzi, rxij, ryij, rzij, rijsq |
396 |
real( kind = DP ) :: rlistsq, rcutsq,rlist,rcut |
397 |
|
398 |
! a rig that need to be fixed. |
399 |
#ifdef IS_MPI |
400 |
logical :: newtons_thrd = .true. |
401 |
real( kind = dp ) :: pe_local |
402 |
integer :: nlocal |
403 |
#endif |
404 |
integer :: nrow |
405 |
integer :: ncol |
406 |
integer :: natoms |
407 |
|
408 |
|
409 |
|
410 |
|
411 |
! Make sure we are properly initialized. |
412 |
if (.not. isljFFInit) then |
413 |
write(default_error,*) "ERROR: lj_FF has not been properly initialized" |
414 |
return |
415 |
endif |
416 |
#ifdef IS_MPI |
417 |
if (.not. isMPISimSet()) then |
418 |
write(default_error,*) "ERROR: mpiSimulation has not been properly initialized" |
419 |
return |
420 |
endif |
421 |
#endif |
422 |
|
423 |
!! initialize local variables |
424 |
natoms = getNlocal() |
425 |
call getRcut(rcut,rcut2=rcutsq) |
426 |
call getRlist(rlist,rlistsq) |
427 |
|
428 |
#ifndef IS_MPI |
429 |
nrow = natoms - 1 |
430 |
ncol = natoms |
431 |
#else |
432 |
nrow = getNrow(plan_row) |
433 |
ncol = getNcol(plan_col) |
434 |
nlocal = natoms |
435 |
j_start = 1 |
436 |
#endif |
437 |
|
438 |
|
439 |
!! See if we need to update neighbor lists |
440 |
call check(q,update_nlist) |
441 |
if (firstTime) then |
442 |
update_nlist = .true. |
443 |
firstTime = .false. |
444 |
endif |
445 |
|
446 |
!--------------WARNING........................... |
447 |
! Zero variables, NOTE:::: Forces are zeroed in C |
448 |
! Zeroing them here could delete previously computed |
449 |
! Forces. |
450 |
!------------------------------------------------ |
451 |
#ifndef IS_MPI |
452 |
! nloops = nloops + 1 |
453 |
pe = 0.0E0_DP |
454 |
|
455 |
#else |
456 |
fRow = 0.0E0_DP |
457 |
fCol = 0.0E0_DP |
458 |
|
459 |
pe_local = 0.0E0_DP |
460 |
|
461 |
eRow = 0.0E0_DP |
462 |
eCol = 0.0E0_DP |
463 |
eTemp = 0.0E0_DP |
464 |
#endif |
465 |
efr = 0.0E0_DP |
466 |
|
467 |
! communicate MPI positions |
468 |
#ifdef IS_MPI |
469 |
call gather(q,qRow,plan_row3d) |
470 |
call gather(q,qCol,plan_col3d) |
471 |
#endif |
472 |
|
473 |
|
474 |
if (update_nlist) then |
475 |
|
476 |
! save current configuration, contruct neighbor list, |
477 |
! and calculate forces |
478 |
call save_nlist(q) |
479 |
|
480 |
nlist = 0 |
481 |
|
482 |
|
483 |
|
484 |
do i = 1, nrow |
485 |
point(i) = nlist + 1 |
486 |
#ifdef IS_MPI |
487 |
ljAtype_i => identPtrListRow(i)%this |
488 |
tag_i = tagRow(i) |
489 |
rxi = qRow(1,i) |
490 |
ryi = qRow(2,i) |
491 |
rzi = qRow(3,i) |
492 |
#else |
493 |
ljAtype_i => identPtrList(i)%this |
494 |
j_start = i + 1 |
495 |
rxi = q(1,i) |
496 |
ryi = q(2,i) |
497 |
rzi = q(3,i) |
498 |
#endif |
499 |
|
500 |
inner: do j = j_start, ncol |
501 |
#ifdef IS_MPI |
502 |
! Assign identity pointers and tags |
503 |
ljAtype_j => identPtrListColumn(j)%this |
504 |
tag_j = tagColumn(j) |
505 |
if (newtons_thrd) then |
506 |
if (tag_i <= tag_j) then |
507 |
if (mod(tag_i + tag_j,2) == 0) cycle inner |
508 |
else |
509 |
if (mod(tag_i + tag_j,2) == 1) cycle inner |
510 |
endif |
511 |
endif |
512 |
|
513 |
rxij = wrap(rxi - qCol(1,j), 1) |
514 |
ryij = wrap(ryi - qCol(2,j), 2) |
515 |
rzij = wrap(rzi - qCol(3,j), 3) |
516 |
#else |
517 |
ljAtype_j => identPtrList(j)%this |
518 |
rxij = wrap(rxi - q(1,j), 1) |
519 |
ryij = wrap(ryi - q(2,j), 2) |
520 |
rzij = wrap(rzi - q(3,j), 3) |
521 |
|
522 |
#endif |
523 |
rijsq = rxij*rxij + ryij*ryij + rzij*rzij |
524 |
|
525 |
#ifdef IS_MPI |
526 |
if (rijsq <= rlistsq .AND. & |
527 |
tag_j /= tag_i) then |
528 |
#else |
529 |
|
530 |
if (rijsq < rlistsq) then |
531 |
#endif |
532 |
|
533 |
nlist = nlist + 1 |
534 |
if (nlist > size(list)) then |
535 |
!! "Change how nlist size is done" |
536 |
write(DEFAULT_ERROR,*) "ERROR: nlist > list size" |
537 |
endif |
538 |
list(nlist) = j |
539 |
|
540 |
|
541 |
if (rijsq < rcutsq) then |
542 |
|
543 |
r = dsqrt(rijsq) |
544 |
|
545 |
call getLJPot(r,pot,dudr,ljAtype_i,ljAtype_j) |
546 |
|
547 |
#ifdef IS_MPI |
548 |
eRow(i) = eRow(i) + pot*0.5 |
549 |
eCol(i) = eCol(i) + pot*0.5 |
550 |
#else |
551 |
pe = pe + pot |
552 |
#endif |
553 |
|
554 |
efr(1,j) = -rxij |
555 |
efr(2,j) = -ryij |
556 |
efr(3,j) = -rzij |
557 |
|
558 |
do dim = 1, 3 |
559 |
|
560 |
|
561 |
drdx1 = efr(dim,j) / r |
562 |
ftmp = dudr * drdx1 |
563 |
|
564 |
|
565 |
#ifdef IS_MPI |
566 |
fCol(dim,j) = fCol(dim,j) - ftmp |
567 |
fRow(dim,i) = fRow(dim,i) + ftmp |
568 |
#else |
569 |
|
570 |
f(dim,j) = f(dim,j) - ftmp |
571 |
f(dim,i) = f(dim,i) + ftmp |
572 |
|
573 |
#endif |
574 |
enddo |
575 |
endif |
576 |
endif |
577 |
enddo inner |
578 |
enddo |
579 |
|
580 |
#ifdef IS_MPI |
581 |
point(nrow + 1) = nlist + 1 |
582 |
#else |
583 |
point(natoms) = nlist + 1 |
584 |
#endif |
585 |
|
586 |
else |
587 |
|
588 |
! use the list to find the neighbors |
589 |
do i = 1, nrow |
590 |
JBEG = POINT(i) |
591 |
JEND = POINT(i+1) - 1 |
592 |
! check thiat molecule i has neighbors |
593 |
if (jbeg .le. jend) then |
594 |
#ifdef IS_MPI |
595 |
ljAtype_i => identPtrListRow(i)%this |
596 |
rxi = qRow(1,i) |
597 |
ryi = qRow(2,i) |
598 |
rzi = qRow(3,i) |
599 |
#else |
600 |
ljAtype_i => identPtrList(i)%this |
601 |
rxi = q(1,i) |
602 |
ryi = q(2,i) |
603 |
rzi = q(3,i) |
604 |
#endif |
605 |
do jnab = jbeg, jend |
606 |
j = list(jnab) |
607 |
#ifdef IS_MPI |
608 |
ljAtype_j = identPtrListColumn(j)%this |
609 |
rxij = wrap(rxi - qCol(1,j), 1) |
610 |
ryij = wrap(ryi - qCol(2,j), 2) |
611 |
rzij = wrap(rzi - qCol(3,j), 3) |
612 |
#else |
613 |
ljAtype_j = identPtrList(j)%this |
614 |
rxij = wrap(rxi - q(1,j), 1) |
615 |
ryij = wrap(ryi - q(2,j), 2) |
616 |
rzij = wrap(rzi - q(3,j), 3) |
617 |
#endif |
618 |
rijsq = rxij*rxij + ryij*ryij + rzij*rzij |
619 |
|
620 |
if (rijsq < rcutsq) then |
621 |
|
622 |
r = dsqrt(rijsq) |
623 |
|
624 |
call getLJPot(r,pot,dudr,ljAtype_i,ljAtype_j) |
625 |
#ifdef IS_MPI |
626 |
eRow(i) = eRow(i) + pot*0.5 |
627 |
eCol(i) = eCol(i) + pot*0.5 |
628 |
#else |
629 |
pe = pe + pot |
630 |
#endif |
631 |
|
632 |
|
633 |
efr(1,j) = -rxij |
634 |
efr(2,j) = -ryij |
635 |
efr(3,j) = -rzij |
636 |
|
637 |
do dim = 1, 3 |
638 |
|
639 |
drdx1 = efr(dim,j) / r |
640 |
ftmp = dudr * drdx1 |
641 |
#ifdef IS_MPI |
642 |
fCol(dim,j) = fCol(dim,j) - ftmp |
643 |
fRow(dim,i) = fRow(dim,i) + ftmp |
644 |
#else |
645 |
f(dim,j) = f(dim,j) - ftmp |
646 |
f(dim,i) = f(dim,i) + ftmp |
647 |
#endif |
648 |
enddo |
649 |
endif |
650 |
enddo |
651 |
endif |
652 |
enddo |
653 |
endif |
654 |
|
655 |
|
656 |
|
657 |
#ifdef IS_MPI |
658 |
!!distribute forces |
659 |
|
660 |
call scatter(fRow,f,plan_row3d) |
661 |
|
662 |
call scatter(fCol,fMPITemp,plan_col3d) |
663 |
|
664 |
do i = 1,nlocal |
665 |
f(1:3,i) = f(1:3,i) + fMPITemp(1:3,i) |
666 |
end do |
667 |
|
668 |
|
669 |
|
670 |
if (do_pot) then |
671 |
|
672 |
! scatter/gather pot_row into the members of my column |
673 |
call scatter(eRow,eTemp,plan_row) |
674 |
|
675 |
! scatter/gather pot_local into all other procs |
676 |
! add resultant to get total pot |
677 |
do i = 1, nlocal |
678 |
pe_local = pe_local + eTemp(i) |
679 |
enddo |
680 |
if (newtons_thrd) then |
681 |
eTemp = 0.0E0_DP |
682 |
call scatter(eCol,eTemp,plan_col) |
683 |
do i = 1, nlocal |
684 |
pe_local = pe_local + eTemp(i) |
685 |
enddo |
686 |
endif |
687 |
|
688 |
pe = pe_local |
689 |
endif |
690 |
#endif |
691 |
|
692 |
potE = pe |
693 |
|
694 |
end subroutine do_lj_ff |
695 |
|
696 |
!! Calculates the potential between two lj particles based on two lj_atype pointers, optionally returns second |
697 |
!! derivatives. |
698 |
subroutine getLjPot(r,pot,dudr,atype1,atype2,d2,status) |
699 |
! arguments |
700 |
!! Length of vector between particles |
701 |
real( kind = dp ), intent(in) :: r |
702 |
!! Potential Energy |
703 |
real( kind = dp ), intent(out) :: pot |
704 |
!! Derivatve wrt postion |
705 |
real( kind = dp ), intent(out) :: dudr |
706 |
!! Second Derivative, optional, used mainly for normal mode calculations. |
707 |
real( kind = dp ), intent(out), optional :: d2 |
708 |
|
709 |
type (lj_atype), pointer :: atype1 |
710 |
type (lj_atype), pointer :: atype2 |
711 |
|
712 |
integer, intent(out), optional :: status |
713 |
|
714 |
! local Variables |
715 |
real( kind = dp ) :: sigma |
716 |
real( kind = dp ) :: sigma2 |
717 |
real( kind = dp ) :: sigma6 |
718 |
real( kind = dp ) :: epsilon |
719 |
|
720 |
real( kind = dp ) :: rcut |
721 |
real( kind = dp ) :: rcut2 |
722 |
real( kind = dp ) :: rcut6 |
723 |
real( kind = dp ) :: r2 |
724 |
real( kind = dp ) :: r6 |
725 |
|
726 |
real( kind = dp ) :: t6 |
727 |
real( kind = dp ) :: t12 |
728 |
real( kind = dp ) :: tp6 |
729 |
real( kind = dp ) :: tp12 |
730 |
real( kind = dp ) :: delta |
731 |
|
732 |
logical :: doSec = .false. |
733 |
|
734 |
integer :: errorStat |
735 |
|
736 |
!! Optional Argument Checking |
737 |
! Check to see if we need to do second derivatives |
738 |
|
739 |
if (present(d2)) doSec = .true. |
740 |
if (present(status)) status = 0 |
741 |
|
742 |
! Look up the correct parameters in the mixing matrix |
743 |
sigma = ljMixed(atype1%atype_ident,atype2%atype_ident)%sigma |
744 |
sigma2 = ljMixed(atype1%atype_ident,atype2%atype_ident)%sigma2 |
745 |
sigma6 = ljMixed(atype1%atype_ident,atype2%atype_ident)%sigma6 |
746 |
epsilon = ljMixed(atype1%atype_ident,atype2%atype_ident)%epsilon |
747 |
|
748 |
|
749 |
|
750 |
|
751 |
call getRcut(rcut,rcut2=rcut2,rcut6=rcut6,status=errorStat) |
752 |
|
753 |
r2 = r * r |
754 |
r6 = r2 * r2 * r2 |
755 |
|
756 |
t6 = sigma6/ r6 |
757 |
t12 = t6 * t6 |
758 |
|
759 |
|
760 |
|
761 |
tp6 = sigma6 / rcut6 |
762 |
tp12 = tp6*tp6 |
763 |
|
764 |
delta = -4.0E0_DP*epsilon * (tp12 - tp6) |
765 |
|
766 |
if (r.le.rcut) then |
767 |
pot = 4.0E0_DP * epsilon * (t12 - t6) + delta |
768 |
dudr = 24.0E0_DP * epsilon * (t6 - 2.0E0_DP*t12) / r |
769 |
if(doSec) d2 = 24.0E0_DP * epsilon * (26.0E0_DP*t12 - 7.0E0_DP*t6)/r/r |
770 |
else |
771 |
pot = 0.0E0_DP |
772 |
dudr = 0.0E0_DP |
773 |
if(doSec) d2 = 0.0E0_DP |
774 |
endif |
775 |
|
776 |
return |
777 |
|
778 |
|
779 |
|
780 |
end subroutine getLjPot |
781 |
|
782 |
|
783 |
!! Calculates the mixing for sigma or epslon based on character string for initialzition of mixing array. |
784 |
function calcLJMix(thisParam,param1,param2,status) result(myMixParam) |
785 |
character(len=*) :: thisParam |
786 |
real(kind = dp) :: param1 |
787 |
real(kind = dp) :: param2 |
788 |
real(kind = dp ) :: myMixParam |
789 |
integer, optional :: status |
790 |
|
791 |
|
792 |
myMixParam = 0.0_dp |
793 |
|
794 |
if (present(status)) status = 0 |
795 |
|
796 |
select case (thisParam) |
797 |
|
798 |
case ("sigma") |
799 |
myMixParam = 0.5_dp * (param1 + param2) |
800 |
case ("epsilon") |
801 |
myMixParam = sqrt(param1 * param2) |
802 |
case default |
803 |
status = -1 |
804 |
end select |
805 |
|
806 |
end function calcLJMix |
807 |
|
808 |
|
809 |
|
810 |
end module lj_ff |