1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
|
#if HAVE_CONFIG_H
# include "config.fh"
#endif
subroutine cluster_com
#include "common.fh"
c
integer i
double precision masstot, dx, dy, dz
double precision r,rdot,com(10)
c
c This subroutine calculates the center of mass (COM) of the cluster of
c particles of type 2, excluding the lone particle.
c
if (nocluster) return
cl_cmx = 0.0d00
cl_cmy = 0.0d00
cl_cmz = 0.0d00
cl_acmx = 0.0d00
cl_acmy = 0.0d00
cl_acmz = 0.0d00
cl_vcmx = 0.0d00
cl_vcmy = 0.0d00
cl_vcmz = 0.0d00
masstot = 0.0d00
c
do i = 1, antot
c if (at(i).eq.2.and.aidx(i).ne.cl_lone_particle) then
if (at(i).eq.2) then
cl_cmx = cl_cmx + mass(i)*ra(i,1,6)
cl_cmy = cl_cmy + mass(i)*ra(i,2,6)
cl_cmz = cl_cmz + mass(i)*ra(i,3,6)
cl_acmx = cl_acmx + ra(i,1,4)
cl_acmy = cl_acmy + ra(i,2,4)
cl_acmz = cl_acmz + ra(i,3,4)
cl_vcmx = cl_vcmx + mass(i)*ra(i,1,2)
cl_vcmy = cl_vcmy + mass(i)*ra(i,2,2)
cl_vcmz = cl_vcmz + mass(i)*ra(i,3,2)
masstot = masstot + mass(i)
endif
end do
com(1) = cl_cmx
com(2) = cl_cmy
com(3) = cl_cmz
com(4) = cl_vcmx
com(5) = cl_vcmy
com(6) = cl_vcmz
com(7) = cl_acmx
com(8) = cl_acmy
com(9) = cl_acmz
com(10) = masstot
call ga_dgop(3,com,10,'+')
cl_cmx = com(1)
cl_cmy = com(2)
cl_cmz = com(3)
cl_acmx = com(7)
cl_acmy = com(8)
cl_acmz = com(9)
cl_vcmx = com(4)
cl_vcmy = com(5)
cl_vcmz = com(6)
masstot = com(10)
if (masstot.gt.0.0d00) then
cl_cmx = cl_cmx / masstot
cl_cmy = cl_cmy / masstot
cl_cmz = cl_cmz / masstot
cl_acmx = cl_acmx / masstot
cl_acmy = cl_acmy / masstot
cl_acmz = cl_acmz / masstot
cl_vcmx = cl_vcmx / masstot
cl_vcmy = cl_vcmy / masstot
cl_vcmz = cl_vcmz / masstot
endif
cl_mass = masstot
c
return
end
c
subroutine cluster_therm
#include "common.fh"
c
integer i
double precision dx, dy, dz
double precision r,rdot
c
c remove component of velocity that lies along the vector from COM
c to the particle, if particle is outside cluster radius. This gradually
c forces particles to form a drop.
c
if (nocluster) return
if (istep.ge.equil_1) return
call cluster_com
do i = 1, antot
c if (at(i).eq.2.and.aidx(i).ne.cl_lone_particle) then
if (at(i).eq.2) then
dx = ra(i,1,1) - cl_cmx
dy = ra(i,2,1) - cl_cmy
dz = ra(i,3,1) - cl_cmz
r = sqrt(dx**2 + dy**2 + dz**2)
dx = dx/r
dy = dy/r
dz = dz/r
if (r.gt.r_cluster) then
rdot = ra(i,1,2)*dx+ra(i,2,2)*dy+ra(i,3,2)*dz
if (rdot.gt.0.0d00) then
ra(i,1,2) = ra(i,1,2) - 2.0d00*rdot*dx
ra(i,2,2) = ra(i,2,2) - 2.0d00*rdot*dy
ra(i,3,2) = ra(i,3,2) - 2.0d00*rdot*dz
endif
endif
endif
end do
c
return
end
c
subroutine cluster_center
#include "common.fh"
c
c move center of mass to origin (only perform this if it is immediately
c followed by a call to update subroutine)
c
integer i,me
logical debug
if (nocluster) return
if (istep.eq.0.or.(mod(istep,ilist).eq.0.and.
+ t_rmndr.eq.0.0d00)) then
me = ga_nodeid()
if (istep.ge.6932366) then
debug = .false.
else
debug = .false.
endif
if (debug) then
write(6,*) me,' mod(istep,ilist) = ',mod(istep,ilist)
write(6,*) me,' ilist = ',ilist
endif
call cluster_com
if (debug) write(6,*) me,'cl_cmx (a) = ',cl_cmx,istep
if (debug) write(6,*) me,'cl_cmy (a) = ',cl_cmy,istep
if (debug) write(6,*) me,'cl_cmz (a) = ',cl_cmz,istep
do i = 1, antot
ra(i,1,6) = ra(i,1,6) - cl_cmx
ra(i,2,6) = ra(i,2,6) - cl_cmy
ra(i,3,6) = ra(i,3,6) - cl_cmz
end do
call fixper
call cluster_com
if (debug) write(6,*) me,'cl_cmx (b) = ',cl_cmx,istep
if (debug) write(6,*) me,'cl_cmy (b) = ',cl_cmy,istep
if (debug) write(6,*) me,'cl_cmz (b) = ',cl_cmz,istep
endif
return
end
c
subroutine cluster_old_at
#include "common.fh"
c
c store original coordinates of cluster atoms
c
integer i, icnt, jcnt
if (nocluster) return
icnt = 0
jcnt = 0
do i = 1, antot
if (at(i).eq.2) then
icnt = icnt + 1
cl_at(icnt) = i
cl_old(icnt,1,1) = ra(i,1,1)
cl_old(icnt,2,1) = ra(i,2,1)
cl_old(icnt,3,1) = ra(i,3,1)
cl_old(icnt,1,2) = ra(i,1,6)
cl_old(icnt,2,2) = ra(i,2,6)
cl_old(icnt,3,2) = ra(i,3,6)
cl_old(icnt,1,3) = ra(i,1,2)
cl_old(icnt,2,3) = ra(i,2,2)
cl_old(icnt,3,3) = ra(i,3,2)
endif
if (at(i).eq.1) then
jcnt = jcnt + 1
sl_at(jcnt) = i
sl_old(jcnt,1,1) = ra(i,1,1)
sl_old(jcnt,2,1) = ra(i,2,1)
sl_old(jcnt,3,1) = ra(i,3,1)
sl_old(jcnt,1,2) = ra(i,1,6)
sl_old(jcnt,2,2) = ra(i,2,6)
sl_old(jcnt,3,2) = ra(i,3,6)
sl_old(jcnt,1,3) = ra(i,1,2)
sl_old(jcnt,2,3) = ra(i,2,2)
sl_old(jcnt,3,3) = ra(i,3,2)
endif
end do
c
cl_cm_old(1) = cl_cmx
cl_cm_old(2) = cl_cmy
cl_cm_old(3) = cl_cmz
cl_vcm_old(1) = cl_vcmx
cl_vcm_old(2) = cl_vcmy
cl_vcm_old(3) = cl_vcmz
c
do i = 1, 3
cl_alen1_old(i) = alen1(i)
cl_alen2_old(i) = alen2(i)
end do
cl_vol1_old = vol1
cl_vol2_old = vol2
cl_box_old(1) = xbox
cl_box_old(2) = ybox
cl_box_old(3) = zbox
cl_scal1_old = scal1
cl_scal2_old = scal2
c
cl_tot = icnt
sl_tot = jcnt
return
end
c
subroutine cluster_check_cllsn
#include "common.fh"
c
c This subroutine checks to see if any of the cluster particles have moved
c beyond the cutoff radius from the center of mass of the cluster. If they
c have, then the initial guess for the particle coordinates and velocities
c is modified to reflect the collision with the restraining sphere.
c
integer icnt, iat, i, j, ii, jj, iloc, imin, scndat, reset
double precision r, r2, rx, ry, rz, dtmax, tsav
double precision rrx, rry, rrz, vvx, vvy, vvz
double precision vn, vx, vy, vz, fx, fy, fz, mu, v2, f2
double precision vrdot, frdot, vfdot, a, b, c
double precision t1, t2, tcut, comm(4), tmax, htausq
double precision rnx, rny, rnz, vpx, vpy, vpz, vllx, vlly, vllz
double precision t3, t4, ax, ay, az, tchk, tmin, t_est
double precision r1x, r1y, r1z, r2x, r2y, r2z, rmax, rskin, rn
double precision cluster_find_tau
integer failsafe, ibuf(MD_MAXPROC), me, nproc, twohit
logical debug
integer iter
c
iter = 0
l_cllsn = .false.
if (nocluster) then
t_rmndr = 0.0d00
t_done = tau
return
endif
me = ga_nodeid()
nproc = ga_nnodes()
if (istep.ge.68365721.and.istep.le.68365723) then
debug = .false.
else
debug = .false.
endif
rskin = 0.02d00
tmax = t_rmndr
if (t_rmndr.eq.tau) cllsn_isav = 0
100 dtmax = 2.0d00*t_rmndr
twohit = 0
failsafe = 0
iat = 0
iloc = 0
tsav = 0.0d00
rmax = r_cluster
if (debug) write(6,*) me,' atot = ',atot,istep
if (debug) write(6,*) me,' antot = ',antot,istep
if (debug) write(6,*) me, ' r_cluster = ',r_cluster,istep
if (debug) write(6,*) me,' t_rmndr = ',tmax,istep
if (debug) write(6,*) me,' cl_cmx(1) = ',cl_cmx,istep
if (debug) write(6,*) me,' cl_cmy(1) = ',cl_cmy,istep
if (debug) write(6,*) me,' cl_cmz(1) = ',cl_cmz,istep
do i = 1, cl_tot
ii = cl_at(i)
rx = ra(ii,1,6) - cl_cmx
ry = ra(ii,2,6) - cl_cmy
rz = ra(ii,3,6) - cl_cmz
r2 = rx**2 + ry**2 + rz**2
r = sqrt(r2)
c if (debug) write(6,*) me, 'ra(ii,1,6) ',ra(ii,1,6),istep
c if (debug) write(6,*) me, 'ra(ii,2,6) ',ra(ii,2,6),istep
c if (debug) write(6,*) me, 'ra(ii,3,6) ',ra(ii,3,6),istep
if (r.gt.r_cluster) then
if (r.gt.rmax) rmax = r
if (debug) write(6,*) me,' tmax = ',tmax,istep
if (debug) write(6,*) me,' dtmax = ',dtmax,istep
if (debug) write(6,*) me,' ii = ',ii,istep
if (debug) write(6,*) me,' antot = ',antot,istep
if (debug) write(6,*) me,' r-r_cluster ',r-r_cluster,istep
if (debug) write(6,*) me,' r_cluster = ',r_cluster,istep
if (debug) write(6,*) me,' sqrt(r2) = ',sqrt(r2),istep
if (debug) write(6,*) me,' ra(1) = ',ra(ii,1,6),istep
if (debug) write(6,*) me,' ra(2) = ',ra(ii,2,6),istep
if (debug) write(6,*) me,' ra(3) = ',ra(ii,3,6),istep
if (debug) write(6,*) me,' cl_cmx = ',cl_cmx,istep
if (debug) write(6,*) me,' cl_cmy = ',cl_cmy,istep
if (debug) write(6,*) me,' cl_cmz = ',cl_cmz,istep
if (debug) write(6,*) me,' r_cluster_old = ',r_cluster_old,
+ istep
if (debug) write(6,*) me,' cl_old(1) = ',cl_old(i,1,2),istep
if (debug) write(6,*) me,' cl_old(2) = ',cl_old(i,2,2),istep
if (debug) write(6,*) me,' cl_old(3) = ',cl_old(i,3,2),istep
if (debug) write(6,*) me,' cl_cm_old(1) = ',cl_cm_old(1),istep
if (debug) write(6,*) me,' cl_cm_old(2) = ',cl_cm_old(2),istep
if (debug) write(6,*) me,' cl_cm_old(3) = ',cl_cm_old(3),istep
if (debug) write(6,*) me,' r_old = ', sqrt(
+ + (cl_old(i,1,2)-cl_cm_old(1))**2
+ + (cl_old(i,2,2)-cl_cm_old(2))**2
+ + (cl_old(i,3,2)-cl_cm_old(3))**2)
rn = sqrt(rx**2+ry**2+rz**2)
vn = ra(ii,1,2)*rx+ra(ii,2,2)*ry+ra(ii,3,2)*rz
vn = vn/rn
t_est = vn*(rn-r_cluster)
tcut = cluster_find_tau(ii,i,cllsn_isav,tmax,.false.)
if (debug) write(6,*) me,' tcut = ',tcut,istep
if (debug) write(6,*) me,' t_est = ',t_est,istep
if (debug) write(6,155) me,1,tcut,istep
155 format(i3,' tcut at ',i1,': ',f12.4,' step: ',i8)
c
c Check to see if collision is earlier than previously found collisions
c and that it is also greater than zero.
c
if (tcut.lt.dtmax.and.tcut.gt.0.0d00) then
c
c Try to protect against numerical roundoff by checking that different
c particle collides with sphere or that collision time is significantly
c greater than zero if it is the same particle
c
if (.not.(ii.eq.cllsn_isav.and.tcut.lt.1.0d-03)) then
dtmax = tcut
tsav = tcut
iat = ii
iloc = i
else
write(6,101) ii, tcut, istep
101 format('Rejected collision of atom ',i8,' at time ',
+ f16.8,' at step ',i8)
failsafe = 1
endif
else if (tcut.lt.0.0d00) then
write(6,*) ga_nodeid(),' vn ',vn,istep
write(6,*) ga_nodeid(),' t_est ',t_est,istep
write(6,*) ga_nodeid(),' r-r_cluster ',r-r_cluster,istep
write(6,*) ga_nodeid(),' Returned negative value at 1',istep
failsafe = 1
endif
#if 0
c
c Check for trajectories that may have gone out and then back into
c confining sphere
c
else if (r_cluster-r.lt.rskin.and.r_cluster-r.gt.0.0d00) then
vn = rx*ra(ii,1,2)+ry*ra(ii,2,2)+rz*ra(ii,3,2)
if (vn.le.0.0d00) then
tcut = cluster_find_tau(ii,i,cllsn_isav,tmax,.true.)
if (tcut.lt.dtmax.and.tcut.gt.0.0d00) then
write(6,*) 'Found looping trajectory',istep
write(6,*) 'dtmax = ',dtmax,istep
write(6,*) 'tcut = ',tcut,istep
write(6,*) 'ii = ',ii,istep
write(6,*) 'cllsn_isav = ',cllsn_isav,istep
write(6,*) 'r = ',r,istep
write(6,*) 'r_cluster = ',r_cluster,istep
if (.not.(ii.eq.cllsn_isav.and.tcut.lt.1.0d-10)) then
write(6,*) 'Resetting trajectory',istep
dtmax = tcut
tsav = tcut
iat = ii
iloc = i
else
write(6,*)'Not resetting trajectory (loop is too short)'
endif
endif
endif
#endif
endif
end do
c
c Check to see if a collision occured on another processor
c
ibuf(1) = iat
ibuf(2) = failsafe
if (debug) write(6,*) me,' iat = ',iat,istep
if (debug) write(6,*) me,' failsafe = ',failsafe,istep
if (debug) write(6,*) me,' ibuf(1) = ',ibuf(1),istep
if (debug) write(6,*) me,' ibuf(2) = ',ibuf(2),istep
call ga_igop(5,ibuf,2,'+')
if (debug) write(6,*) me,' ibuf(1) = ',ibuf(1),istep
if (debug) write(6,*) me,' ibuf(2) = ',ibuf(2),istep
c
c No collisions detected. Step is complete so just return.
c
if (ibuf(1).eq.0.and.ibuf(2).eq.0) then
t_rmndr = 0.0d00
t_done = tau
if (debug) write(6,*) me,' Returning with no hits ',istep
return
endif
c
c If no solution found for atom outside confining sphere, then bail
c completely and increase diameter of confining sphere so that all
c atoms are enclosed.
c
if (ibuf(2).gt.0) then
call ga_dgop(4,rmax,1,'max')
if (debug) write(6,*) me,' r_cluster (a) = ',r_cluster
r_cluster = r_cluster + (rmax - r_cluster)*1.1d00
if (debug) write(6,*) me,' r_cluster (b) = ',r_cluster
if (ga_nodeid().eq.0) then
write(6,*) ga_nodeid(),' Returned negative value at 2',istep
endif
failcount = failcount + 1
t_rmndr = 0.0d00
t_done = tau
return
endif
c
c At this point, a collision has been detected on at least on
c processor. Check to find minimum time if collisions occur on more
c than one processor.
c
if (iat.eq.0) then
tsav = tau
endif
a = tsav
call ga_dgop(6,a,1,'min')
c
c Find mass of particle that has first collision with confining sphere
c
if (a.eq.tsav) then
b = mass(iat)
else
b = 0.0d00
endif
call ga_dgop(7,b,1,'max')
1000 mmass = cl_mass - b
tcut = a
if (debug) write(6,155) me,2,tcut,istep
if (tsav.ne.a) then
iat = 0
iloc = 0
cllsn_isav = 0
if (debug) write(6,*) me,' cllsn_isav(1): ',cllsn_isav
else
cllsn_isav = iat
if (debug) write(6,*) me,' cllsn_isav(2): ',cllsn_isav
endif
c
c Handle degenerate case of only two atoms in cluster, which will
c generally have two simultaneous collisions
c
if (ctot.eq.2) then
do i = 1, nproc
if (i-1.eq.me) then
ibuf(i) = iat
else
ibuf(i) = 0
endif
end do
call ga_igop(3,ibuf,nproc,'+')
j = 0
iat = 0
cllsn_isav = 0
do i = 1, nproc
if (ibuf(i).gt.0.and.i-1.eq.me.and.j.eq.0) then
iat = ibuf(i)
cllsn_isav = ibuf(i)
j = 1
else if (ibuf(i).gt.0) then
j = 1
endif
end do
c
c Make sure that correct mass is being used for collision
c
if (iat.ne.0) then
b = mass(iat)
else
b = 0.0d00
endif
call ga_dgop(6,b,1,'max')
mmass = cl_mass - b
endif
c
c Now recalculate coordinates of all particles in the cluster
c
call cluster_reset(tcut)
call cluster_com !CHECK
c
c Check to see if there were any trajectories that pass through confining
c sphere twice (i.e. goes out and then comes back in). Don't bother with
c check if there are only 2 particles in system.
c
if (ctot.eq.2) then
go to 2000
endif
reset = 0
tchk = 0.0d00
scndat = 0
tmin = tcut
tsav = tcut
failsafe = 0
do i = 1, cl_tot
ii = cl_at(i)
rx = ra(ii,1,6) - cl_cmx
ry = ra(ii,2,6) - cl_cmy
rz = ra(ii,3,6) - cl_cmz
r = sqrt(rx**2+ry**2+rz**2)
if (r.ge.r_cluster.and.ii.ne.cllsn_isav) then
tchk = cluster_find_tau(ii,i,cllsn_isav,tcut,.false.)
if (debug) write(6,155) me,7,tchk,istep
if (debug) write(6,*) me, 'ii: ',ii
if (debug) write(6,*) me, 'cllsn_isav: ',cllsn_isav
reset = 1
if (tchk.lt.tmin.and.tchk.gt.0.0d00) then
if (debug) write(6,*) me,' Shorter collision found'
tmin = tchk
imin = ii
if (debug) write(6,155) me,4,tchk,istep
if (debug) write(6,155) me,5,tmin,istep
else if (tchk.lt.0.0d00) then
write(6,*) ga_nodeid(),' Returned negative value at 3',istep
failsafe = 1
else
c
c This case should theoretically be impossible, but it may occur because of
c roundoff
c
write(6,*) me,' tchk greater than or equal to tmin',istep
write(6,*) me,' tchk = ',tchk,istep
write(6,*) me,' tmin = ',tmin,istep
failsafe = 1
endif
endif
end do
ibuf(1) = reset
ibuf(2) = failsafe
call ga_igop(2,ibuf,2,'+')
c
c No solution for tau found, so increase confining sphere and then bail
c
if (ibuf(2).gt.0) then
if (debug) write(6,*) me,' rmax (c) = ',rmax
call ga_dgop(4,rmax,1,'max')
if (debug) write(6,*) me,' rmax (d) = ',rmax
if (debug) write(6,*) me,' r_cluster (c) = ',r_cluster
r_cluster = r_cluster + (rmax - r_cluster)*1.1d00
if (debug) write(6,*) me,' r_cluster (d) = ',r_cluster
if (ga_nodeid().eq.0) then
write(6,*) 'Bogus value of collision time at 2'
endif
call cluster_reset(t_rmndr)
t_rmndr = 0.0d00
t_done = tau
return
endif
reset = ibuf(1)
c
c Shorter collision found so recalculate positions
c
if (reset.gt.0) then
if (tmin.le.tsav) then
if (debug) write(6,*) 'tmin = ',tmin,istep
if (debug) write(6,*) 'tsav = ',tsav,istep
a = tmin
else
a = tau
endif
call ga_dgop(2,a,1,'min')
c
if (a.le.tsav) then
if (a.ne.tmin) then
iat = 0
iloc = 0
cllsn_isav = 0
if (debug) write(6,*) me,'cllsn_isav(3): ',cllsn_isav
else
cllsn_isav = imin
if (debug) write(6,*) me,'cllsn_isav(4): ',cllsn_isav
endif
tcut = a
tsav = a !BJP is this correct?
if (debug) write(6,155) me,3,tcut,istep
if (iat.gt.0) then
b = mass(iat)
else
b = 0.0d00
endif
call ga_dgop(7,b,1,'+')
call cluster_reset(0.0d00)
iter = iter + 1
if (iter.gt.100) debug = .true.
if (iter.gt.1000) call ga_error('Too many iterations',0)
go to 1000
endif
endif
c
2000 l_cllsn = .true.
cllsn_idx = cllsn_isav
c
t_rmndr = tmax - tcut
t_done = tau - t_rmndr
if (debug) write(6,*) me, 't_rmndr = ',t_rmndr
if (debug) write(6,*) me, 't_done = ',t_done
c
return
end
c
double precision function cluster_find_tau(iat,iloc,isav,tmax,
+ forward)
#include "common.fh"
c
c This function calculates the time at which a particle outside the confining
c sphere would have collided with the sphere.
c
integer iat, iloc, isav
double precision r, r2, rx, ry, rz, dr
double precision rrx, rry, rrz, vvx, vvy, vvz
double precision vx, vy, vz, fx, fy, fz, v2, f2
double precision clcut, frdot, vrdot, vfdot, a, b, c
double precision t, t1, t2, tcut, tmax, thi, tlo, tmid
double precision ttmin,ttmax
integer i,j,me,iter
logical forward, debug
c
c A particle lies outside the cutoff. Find particle that crosses
c cutoff first.
c
if (istep.ge.68365721.and.istep.le.68365723) then
debug = .false.
else
debug = .false.
endif
me = ga_nodeid()
mmass = cl_mass - mass(iat)
c
c Calculate center of mass and velocity of center of mass of remaining
c particles in cluster (these are the rr and vv vectors)
c
rrx = (cl_mass*cl_cm_old(1) - mass(iat)*cl_old(iloc,1,2))/mmass
rry = (cl_mass*cl_cm_old(2) - mass(iat)*cl_old(iloc,2,2))/mmass
rrz = (cl_mass*cl_cm_old(3) - mass(iat)*cl_old(iloc,3,2))/mmass
vvx = (cl_mass*cl_vcm_old(1) - mass(iat)*cl_old(iloc,1,3))/mmass
vvy = (cl_mass*cl_vcm_old(2) - mass(iat)*cl_old(iloc,2,3))/mmass
vvz = (cl_mass*cl_vcm_old(3) - mass(iat)*cl_old(iloc,3,3))/mmass
c
c The r and v vectors are the relative coordinates and velocities of
c particle iat and the center of mass vectors. The vector f is the
c force along this relative coordinate.
c
rx = cl_old(iloc,1,2) - cl_cm_old(1)
ry = cl_old(iloc,2,2) - cl_cm_old(2)
rz = cl_old(iloc,3,2) - cl_cm_old(3)
vx = cl_old(iloc,1,3) - cl_vcm_old(1)
vy = cl_old(iloc,2,3) - cl_vcm_old(2)
vz = cl_old(iloc,3,3) - cl_vcm_old(3)
fx = ra(iat,1,3) - cl_acmx
fy = ra(iat,2,3) - cl_acmy
fz = ra(iat,3,3) - cl_acmz
c
r = sqrt(rx**2 + ry**2 + rz**2)
c
c Note that we are using acceleration instead of force,
c so factors of reduced mass disappear
c
vrdot = vx*rx + vy*ry + vz*rz
frdot = fx*rx + fy*ry + fz*rz
vfdot = vx*fx + vy*fy + vz*fz
clcut = r_cluster
v2 = vx**2 + vy**2 + vz**2
a = v2+frdot
b = 2.0d00*vrdot
c
c c = rx**2 + ry**2 + rz**2 - clcut**2
c
c Calculate c to minimize roundoff error from subtracting large numbers
c
dr = r - clcut
c = 2.0d00*r*dr+dr**2
f2 = fx**2 + fy**2 + fz**2
c
c Scan forwards from 0 to find a final value of t2. If no final
c value found, then return with value of -1.
c
if (debug) write(6,*) me, 'iat: ',iat
if (debug) write(6,*) me, 'a: ',a
if (debug) write(6,*) me, 'b: ',b
if (debug) write(6,*) me, 'c: ',c
if (debug) write(6,*) me, 'f2: ',f2
if (debug) write(6,*) me, 'vfdot: ',vfdot
if (forward) then
t = tmax
t1 = 0.0d00
ttmin = t1
ttmax = t
c tlo = c + t1*(b + t1*(a+t1*(vfdot+t1*0.25d00*f2)))
tlo = (-c-t1**2*(a+t1*(vfdot+t1*0.25d00*f2)))/b - t1
do i = 1, 1000
if (t.eq.tmax) then
t2= tmax*dble(i)/1000.0d00
c thi = c + t2*(b + t2*(a+t2*(vfdot+t2*0.25d00*f2)))
thi = (-c-t2**2*(a+t2*(vfdot+t2*0.25d00*f2)))/b - t2
if ((thi.ge.0.0d00.and.tlo.le.0.0d00).or.
+ (thi.le.0.0d00.and.tlo.ge.0.0d00)) then
t = t2
write(6,*) ga_nodeid(),' tmin = ',ttmin,istep
write(6,*) ga_nodeid(),' tmax = ',ttmax,istep
write(6,*) ga_nodeid(),' tlo = ',tlo,istep
write(6,*) ga_nodeid(),' thi = ',thi,istep
write(6,*) ga_nodeid(),' t = ',t,istep
go to 500
endif
endif
end do
cluster_find_tau = -1.0d00
return
c
c scan backwards from tmax to find an initial value of t1
c
else
t = 0.0d00
t2 = tmax
c thi = c + t2*(b + t2*(a+t2*(vfdot+t2*0.25d00*f2)))
thi = (-c-t2**2*(a+t2*(vfdot+t2*0.25d00*f2)))/b - t2
do i = 1, 1000
if (t.eq.0.0d00) then
t1= tmax - tmax*dble(i)/1000.0d00
c tlo = c + t1*(b + t1*(a+t1*(vfdot+t1*0.25d00*f2)))
tlo = (-c-t1**2*(a+t1*(vfdot+t1*0.25d00*f2)))/b - t1
if ((thi.ge.0.0d00.and.tlo.le.0.0d00).or.
+ (thi.le.0.0d00.and.tlo.ge.0.0d00)) then
t = t1
if (debug) write(6,*) me, 'tlo: ',tlo
if (debug) write(6,*) me, 'thi: ',thi
if (debug) write(6,*) me, 't: ',t
go to 500
endif
endif
end do
endif
c
c Use bisections to find accurate solution
c
500 if (forward) then
t1 = 0.0d00
t2 = t
else
t1 = t
t2 = tmax
if (debug) write(6,*) me, 't1: ',t1
if (debug) write(6,*) me, 't2: ',t2
endif
iter = 0
c 600 tlo = c + t1*(b + t1*(a+t1*(vfdot+t1*0.25d00*f2)))
c thi = c + t2*(b + t2*(a+t2*(vfdot+t2*0.25d00*f2)))
600 tlo = (-c-t1**2*(a+t1*(vfdot+t1*0.25d00*f2)))/b - t1
thi = (-c-t2**2*(a+t2*(vfdot+t2*0.25d00*f2)))/b - t2
if ((thi.ge.0.0d00.and.tlo.le.0.0d00).or.
+ (thi.le.0.0d00.and.tlo.ge.0.0d00)) then
t = 0.5d00*(t1+t2)
c tmid = c + t*(b + t*(a+t*(vfdot+t*0.25d00*f2)))
tmid = (-c-t**2*(a+t*(vfdot+t*0.25d00*f2)))/b - t
if ((tmid.ge.0.0d00.and.thi.le.0.0d00).or.
+ (tmid.le.0.0d00.and.thi.ge.0.0d00)) then
t1 = t
else if ((tmid.ge.0.0d00.and.tlo.le.0.0d00).or.
+ (tmid.le.0.0d00.and.tlo.ge.0.0d00)) then
t2 = t
endif
tcut = 0.5d00*(t1+t2)
iter = iter + 1
if (abs(t1-t2)/tau.gt.1.0d-14.and.iter.lt.1000) go to 600
c
c Protect against numerical roundoff errors
c
if (iter.ge.1000) then
write(6,*) ga_nodeid(),' Maxed out on iterations'
endif
if (forward.and.(tcut.lt.1.0d-10.or.
+ abs(tcut-tmax).lt.1.0d-10)) then
cluster_find_tau = -1.0d00
return
endif
else
open(unit=2,file='tau.dat',status='unknown')
do j = 0, 1000
t = tmax*dble(j)/1000.0d00
t1 = (-c-t**2*(a+t*(vfdot+t*0.25d00*f2)))/b - t
tmid = c + t*(b + t*(a+t*(vfdot+t*0.25d00*f2)))
write(2,300) t,t1, tmid
300 format(3(' ',f16.8))
end do
close(2)
if (iat.ne.isav) then
if (abs(thi).lt.0.000001d00) then
tcut = tmax
else if (abs(tlo).lt.0.000001d00) then
if (vrdot.gt.0.0d00) then
tcut = 0.0d00
else
tcut = tmax
endif
else
if (forward) write(6,*) 'Searching forward'
write(6,*) 'Collision time does not converge at step ',istep
tcut = -1.0d00
endif
else
tcut = 4.0d00*tau
endif
endif
c
if (forward) write(6,*) ga_nodeid(),' tcut = ',tcut
cluster_find_tau = tcut
return
end
c
double precision function cluster_check_radius()
#include "common.fh"
double precision rx, ry, rz, r2, cl2
integer i
c
c check to make sure that all cluster particles are within cluster
c radius
c
cl2 = 0.0d00
do i = 1, antot
if (at(i).eq.2) then
rx = ra(i,1,6) - cl_cmx
ry = ra(i,2,6) - cl_cmy
rz = ra(i,3,6) - cl_cmz
r2 = rx**2 + ry**2 + rz**2
if (r2.gt.cl2) cl2 = r2
endif
end do
call ga_dgop(4,cl2,1,'max')
c
cluster_check_radius = sqrt(cl2)
return
end
c
subroutine cluster_mc
#include "common.fh"
c
c Perform Monte Carlo adjustment of volume on confining volume
c
double precision r_old, delta_r, r2, cl2, rx, ry, rz, pi
double precision vol_new, vol_old, x, ran1, ratio
integer i, icnt, iat, me
logical force_move,debug
c
if (nocluster) return
if (istep.ge.6932366) then
debug = .false.
else
debug = .false.
endif
call cluster_com
me = ga_nodeid()
r_cluster_old = r_cluster
r_old = r_cluster
force_move = .false.
delta_r = 0.2
if (debug) write(6,*)me,' (1) r_cluster ',r_cluster,istep
if (me.eq.0) then
r_cluster = r_cluster + delta_r*(ran1(0)-0.5d00)
else
r_cluster = 0.0d00
endif
if (debug) write(6,*)me,' (2) r_cluster ',r_cluster,istep
call ga_dgop(1,r_cluster,1,'+')
if (debug) write(6,*)me,' (3) r_cluster ',r_cluster,istep
c
c If new value of r_cluster falls outside of allowed interval then
c it is rejected, unless old value was aready outside interval.
c
if (r_cluster.ge.cl_upper.or.r_cluster.le.cl_lower) then
c
c If new values move cluster radius closer to cutoffs from the outside,
c then accept them, reject them otherwise. Before accepting move, make
c sure that there are no illegal overlaps.
c
force_move = .true.
if (r_cluster.gt.r_old.and.r_cluster.gt.cl_upper) then
r_cluster = r_old
else if (r_cluster.lt.r_old.and.r_cluster.lt.cl_lower) then
r_cluster = r_old
endif
if (r_cluster.eq.r_old) return
endif
if (debug) write(6,*)me,' (4) r_cluster ',r_cluster,istep
c
c Check to see if any particles are outside new value of r_cluster.
c If so, then new value is rejected.
c
if (r_cluster.lt.r_old) then
icnt = 0
cl2 = r_cluster**2
do i = 1, antot
if (at(i).eq.2) then
rx = ra(i,1,6) - cl_cmx
ry = ra(i,2,6) - cl_cmy
rz = ra(i,3,6) - cl_cmz
r2 = rx**2 + ry**2 + rz**2
if (r2.gt.cl2) then
icnt = icnt + 1
endif
endif
end do
call ga_igop(9,icnt,1,'+')
if (icnt.gt.0) then
r_cluster = r_old
return
endif
endif
if (debug) write(6,*)me,' (5) r_cluster ',r_cluster,istep
if (force_move) return
c
c Accept with Monte Carlo probability.
c
pi = 4.0d00*atan(1.0d00)
vol_new = 4.0d00*pi*r_cluster**3/3.0d00
vol_old = 4.0d00*pi*r_old**3/3.0d00
ratio = (r_cluster/r_old)**2
c
x = ratio*exp(-cl_prssr*(vol_new-vol_old)/mc_tmprtr)
if (me.eq.0) then
if (x.ge.1.0d00) then
icnt = 1
else
if (ran1(0).lt.x) then
icnt = 1
else
icnt = 0
endif
endif
else
icnt = 0
endif
call ga_igop(1,icnt,1,'+')
if (icnt.eq.0) then
r_cluster = r_old
endif
if (debug) write(6,*)me,' (6) r_cluster ',r_cluster,istep
return
end
c
subroutine cluster_binr
#include "common.fh"
c
c Bin the current value of r_cluster
c
double precision dr
integer ir, isample
if (nocluster) return
c
c Find bin
c
dr = r_cluster - cl_lower
ir = int(dr/mc_step) + 1
if (ir.le.0) ir = 1
if (ir.gt.mcbins) ir = mcbins
mc_cnt = mc_cnt + 1
c
c Find slice for statistics
c
if (istep.gt.mc_start) then
isample = int(10.0d00*(dble(istep-mc_start)-0.5d00)
+ / dble(nstep-mc_start)) + 1
if (isample.gt.10) isample = 10
else
isample = 1
endif
r_cnt(isample) = r_cnt(isample) + 1
r_distr(ir,isample) = r_distr(ir,isample) + 1
return
end
c
subroutine cluster_print_binr
#include "common.fh"
c
c Print out the distribution of r_cluster
c
double precision rdist(MAXBINS), norm, r, normi
double precision rdist2(MAXBINS), sum
double precision sigr(MAXBINS),sigr2(MAXBINS)
double precision sig2(MAXBINS),sig2_2(MAXBINS)
double precision rdisti(MAXBINS,10),rdisti2(MAXBINS,10)
integer itot, i, j, isample
character*32 filename
c
if (nocluster) return
if (task_id.lt.10) then
write(filename,100) task_id
else if (task_id.ge.10.and.task_id.lt.100) then
write(filename,101) task_id
else if (task_id.ge.100.and.task_id.lt.1000) then
write(filename,102) task_id
else if (task_id.ge.1000.and.task_id.lt.10000) then
write(filename,103) task_id
endif
100 format('cl.distr.',i1)
101 format('cl.distr.',i2)
102 format('cl.distr.',i3)
103 format('cl.distr.',i4)
c
c Evaluate normalized distribution and uncertainty for P(r)
c
if (mc_cnt.lt.0) return
norm = dble(mc_cnt)
do i = 1, mcbins
rdist(i) = 0.0d00
rdist2(i) = 0.0d00
sig2(i) = 0.0d00
sig2_2(i) = 0.0d00
sigr(i) = 0.0d00
sigr2(i) = 0.0d00
do j = 1, 10
rdisti(i,j) = 0.0d00
rdisti2(i,j) = 0.0d00
end do
end do
do j = 1, 10
normi = dble(r_cnt(j))
do i = 1, mcbins
rdist(i) = rdist(i) + dble(r_distr(i,j))/norm
rdisti(i,j) = dble(r_distr(i,j))/normi
end do
end do
do j = 1, 10
do i = 1, mcbins
sig2(i) = sig2(i) + rdisti(i,j)**2
end do
end do
do i = 1, mcbins
sigr(i) = (sig2(i)-10.0d00*rdist(i)**2)/9.0d00
end do
c
c Uncertainty at the 95% confidence level
c
do i = 1, mcbins
sigr(i) = 2.23d00*sqrt(sigr(i)/10.d00)
end do
sum = 0.0d00
do i = 1, mcbins
sum = sum + rdist(i)
end do
do i = 1, mcbins
rdist(i) = rdist(i)/(sum*mc_step)
sigr(i) = sigr(i)/(sum*mc_step)
end do
c
c Evaluate normalized distribution and uncertainty for P(V)
c
do j = 1, 10
normi = dble(r_cnt(j))
do i = 1, mcbins
r = cl_lower + (dble(i)-0.5d00)*mc_step
rdist2(i) = rdist2(i) + dble(r_distr(i,j))/(r**2*norm)
rdisti2(i,j) = dble(r_distr(i,j))/(r**2*normi)
end do
end do
do j = 1, 10
do i = 1, mcbins
sig2_2(i) = sig2_2(i) + rdisti2(i,j)**2
end do
end do
do i = 1, mcbins
sigr2(i) = (sig2_2(i)-10.0d00*rdist2(i)**2)/9.0d00
end do
c
c Uncertainty at the 95% confidence level
c
do i = 1, mcbins
sigr2(i) = 2.23d00*sqrt(sigr2(i)/10.d00)
end do
sum = 0.0d00
do i = 1, mcbins
sum = sum + rdist2(i)
end do
do i = 1, mcbins
rdist2(i) = rdist2(i)/(sum*mc_step)
sigr2(i) = sigr2(i)/(sum*mc_step)
end do
c
if (ga_nodeid().eq.0) then
open(unit=2,file=filename,status='unknown')
do i = 1, mcbins
r = cl_lower + (dble(i)-0.5d00)*mc_step
write(2,200) r, rdist(i), rdist2(i),sigr(i),sigr2(i)
200 format(f12.4,' ',f16.8,' ',f16.8,' ',
+ f16.8,' 'f16.8)
end do
close(2)
endif
c
return
end
c
subroutine cluster_clear_binr
#include "common.fh"
c
c clear the distribution of r_cluster
c
integer itot, i, j
c
if (nocluster) return
do j = 1, 10
do i = 1, MAXBINS
r_distr(i,j) = 0
end do
r_cnt(j) = 0
end do
mc_cnt = 0
mc_start = istep
c
return
end
c
subroutine cluster_reset_binr(iflg)
#include "common.fh"
c
c recalculate bounds for confining sphere
c
integer iflg,ilow,ihi,imax,i
if (nocluster) return
if (iflg.eq.1) then
c
c find minimum and maximum values of distribution and reset
c windows to just bound these values
c
if (ga_nodeid().eq.0.and.l_rad) then
open(unit=3,file="win1.dat",status='unknown')
do i = 1, mcbins
write(3,*) i, r_distr(i,1)
end do
endif
ilow = 0
ihi = 0
do i = 1, mcbins
if (r_distr(i,1).gt.0.and.ilow.eq.0) then
ilow = i-1
if (ilow.lt.1) ilow = 1
endif
if (ilow.gt.0.and.ihi.eq.0.and.r_distr(i,1).eq.0) then
ihi = i
endif
end do
if (ihi.eq.0) ihi = mcbins
if (ihi.lt.mcbins) then
cl_upper = cl_lower + mc_step*dble(ihi)
endif
if (ihi.gt.1) then
cl_lower = cl_lower + mc_step*dble(ilow-1)
endif
else if (iflg.eq.2) then
c
c reset bounds so that maximum is set at radius value that
c is the maximum value of distribution
c
ilow = 1
ihi = 0
imax = 0
do i = 1, mcbins
c if (r_distr(i,1).gt.0.and.ilow.eq.0) then
c ilow = i-1
c if (ilow.lt.1) ilow = 1
c endif
if (r_distr(i,1).gt.imax) then
ihi = i
imax = r_distr(i,1)
endif
end do
if (ihi.eq.0) ihi = mcbins
if (ihi.lt.mcbins) then
cl_upper = cl_lower + mc_step*dble(ihi)
endif
if (ilow.gt.1) then
cl_lower = cl_lower + mc_step*dble(ilow-1)
endif
endif
cl_upper = 3.5d00
cl_lower = 0.5d00
cl_upper = 4.5d00
cl_lower = 0.5d00
mc_step = (cl_upper-cl_lower)/dble(mcbins)
call cluster_clear_binr
return
end
c
subroutine cluster_do_cllsn
#include "common.fh"
integer iat, i, j, ii, jj, iloc, isav, scndat
double precision r, r2, rc2, rx, ry, rz
double precision rrx, rry, rrz, vvx, vvy, vvz
double precision vx, vy, vz, fx, fy, fz, mu, v2, f2
double precision comm(4), tmax, tcut, vrdot
double precision rnx, rny, rnz, vpx, vpy, vpz, vllx, vlly, vllz
c
c Re-evaluate all particle velocities. First, recalculate center of
c mass and center of mass velocity of cluster at new coordinates
c and velocities.
c
if (nocluster) return
cllsn_cnt = cllsn_cnt + 1
iat = cllsn_idx
call cluster_com
if (iat.gt.0) then
rrx = (cl_mass*cl_cmx - mass(iat)*ra(iat,1,6))/mmass
rry = (cl_mass*cl_cmy - mass(iat)*ra(iat,2,6))/mmass
rrz = (cl_mass*cl_cmz - mass(iat)*ra(iat,3,6))/mmass
vvx = (cl_mass*cl_vcmx - mass(iat)*ra(iat,1,2))/mmass
vvy = (cl_mass*cl_vcmy - mass(iat)*ra(iat,2,2))/mmass
vvz = (cl_mass*cl_vcmz - mass(iat)*ra(iat,3,2))/mmass
c
c The r and v vectors are the relative coordinates and velocities of
c particle iat and the center of mass vectors. The vector f is the
c force along this relative coordinate.
c
rx = ra(iat,1,6) - rrx
ry = ra(iat,2,6) - rry
rz = ra(iat,3,6) - rrz
vx = ra(iat,1,2) - vvx
vy = ra(iat,2,2) - vvy
vz = ra(iat,3,2) - vvz
c
c Decompose velocity v into components that are parallel and perpendicular
c to r. Save this information for computing post-collision velocities.
c
r = sqrt(rx**2 + ry**2 + rz**2)
rnx = rx/r
rny = ry/r
rnz = rz/r
vrdot = vx*rnx + vy*rny + vz*rnz
vllx = vrdot * rnx
vlly = vrdot * rny
vllz = vrdot * rnz
vpx = vx - vllx
vpy = vy - vlly
vpz = vz - vllz
comm(1) = (vpx-vllx-vx)/cl_mass
comm(2) = (vpy-vlly-vy)/cl_mass
comm(3) = (vpz-vllz-vz)/cl_mass
comm(4) = mmass
else
comm(1) = 0.0d00
comm(2) = 0.0d00
comm(3) = 0.0d00
comm(4) = 0.0d00
endif
call ga_dgop(8,comm,4,'+')
vvx = comm(1)
vvy = comm(2)
vvz = comm(3)
mmass = comm(4)
c
do i = 1, cl_tot
ii = cl_at(i)
if (ii.eq.iat) then
ra(ii,1,2) = ra(ii,1,2) + mmass*vvx
ra(ii,2,2) = ra(ii,2,2) + mmass*vvy
ra(ii,3,2) = ra(ii,3,2) + mmass*vvz
else
ra(ii,1,2) = ra(ii,1,2) - mass(ii)*vvx
ra(ii,2,2) = ra(ii,2,2) - mass(ii)*vvy
ra(ii,3,2) = ra(ii,3,2) - mass(ii)*vvz
endif
end do
call cluster_old_at
c
return
end
c
subroutine cluster_reset(dt)
#include "common.fh"
double precision dt, htausq, scale
integer i, ii
c
c Reset coordinates and velocities using old values from beginning of
c step.
c
htausq = 0.5d00*dt**2
do i = 1, cl_tot
ii = cl_at(i)
ra(ii,1,1) = cl_old(i,1,1)+dt*cl_old(i,1,3)+htausq*ra(ii,1,3)
ra(ii,2,1) = cl_old(i,2,1)+dt*cl_old(i,2,3)+htausq*ra(ii,2,3)
ra(ii,3,1) = cl_old(i,3,1)+dt*cl_old(i,3,3)+htausq*ra(ii,3,3)
ra(ii,1,6) = cl_old(i,1,2)+dt*cl_old(i,1,3)+htausq*ra(ii,1,3)
ra(ii,2,6) = cl_old(i,2,2)+dt*cl_old(i,2,3)+htausq*ra(ii,2,3)
ra(ii,3,6) = cl_old(i,3,2)+dt*cl_old(i,3,3)+htausq*ra(ii,3,3)
ra(ii,1,2) = cl_old(i,1,3)+dt*ra(ii,1,3)
ra(ii,2,2) = cl_old(i,2,3)+dt*ra(ii,2,3)
ra(ii,3,2) = cl_old(i,3,3)+dt*ra(ii,3,3)
end do
#if 1
do i = 1, sl_tot
ii = sl_at(i)
ra(ii,1,1) = sl_old(i,1,1)+dt*sl_old(i,1,3)+htausq*ra(ii,1,3)
ra(ii,2,1) = sl_old(i,2,1)+dt*sl_old(i,2,3)+htausq*ra(ii,2,3)
ra(ii,3,1) = sl_old(i,3,1)+dt*sl_old(i,3,3)+htausq*ra(ii,3,3)
ra(ii,1,6) = sl_old(i,1,2)+dt*sl_old(i,1,3)+htausq*ra(ii,1,3)
ra(ii,2,6) = sl_old(i,2,2)+dt*sl_old(i,2,3)+htausq*ra(ii,2,3)
ra(ii,3,6) = sl_old(i,3,2)+dt*sl_old(i,3,3)+htausq*ra(ii,3,3)
ra(ii,1,2) = sl_old(i,1,3)+dt*ra(ii,1,3)
ra(ii,2,2) = sl_old(i,2,3)+dt*ra(ii,2,3)
ra(ii,3,2) = sl_old(i,3,3)+dt*ra(ii,3,3)
end do
#endif
#if 1
c
c resete extended Hamiltonian parameters
c
if ((prsflg.or.ptflg).and.ipmode.eq.0) then
vol1 = cl_vol1_old + dt * cl_vol2_old + htausq * vol3
vol2 = cl_vol2_old + dt * vol3
scale = vol1 / (cl_box_old(1) * cl_box_old(2) * cl_box_old(3))
scale = exp(log(scale)/3.0d00)
xbox = scale * cl_box_old(1)
ybox = scale * cl_box_old(2)
zbox = scale * cl_box_old(3)
xbox2 = 0.5d00 * xbox
ybox2 = 0.5d00 * ybox
zbox2 = 0.5d00 * zbox
endif
c
if ((prsflg.or.ptflg).and.ipmode.eq.1) then
do 500 i = 1, 3
alen1(i) = cl_alen1_old(i) + dt * cl_alen2_old(i)
+ + htausq * alen3(i)
alen2(i) = cl_alen2_old(i) + dt * alen3(i)
500 continue
xbox = alen1(1)
ybox = alen1(2)
zbox = alen1(3)
xbox2 = 0.5d00 * xbox
ybox2 = 0.5d00 * ybox
zbox2 = 0.5d00 * zbox
endif
c
if ((prsflg.or.ptflg).and.ipmode.eq.2) then
do 600 i = 1, 2
alen1(i) = cl_alen1_old(i) + dt * cl_alen2_old(i)
+ + htausq * alen3(i)
alen2(i) = cl_alen2_old(i) + dt * alen3(i)
600 continue
xbox = alen1(1)
ybox = alen1(2)
xbox2 = 0.5d00 * xbox
ybox2 = 0.5d00 * ybox
endif
c
c predictor step for time scale
c
if (tmpflg.or.ptflg) then
scal1 = cl_scal1_old + dt * cl_scal2_old + htausq * scal3
scal2 = cl_scal2_old + dt * scal3
endif
c
c center of mass parameters
c
cl_cmx = cl_cm_old(1)
cl_cmy = cl_cm_old(2)
cl_cmz = cl_cm_old(3)
cl_vcmx = cl_vcm_old(1)
cl_vcmy = cl_vcm_old(2)
cl_vcmz = cl_vcm_old(3)
#endif
return
end
|
