src/gromacs/ewald/long-range-correction.cpp

   1 /*
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   3  *
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   5  * Copyright (c) 2001-2004, The GROMACS development team.
   6  * Copyright (c) 2013,2014,2015,2016,2017,2018, by the GROMACS development team, led by
   7  * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
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  37 #include "gmxpre.h"
  38
  39 #include "long-range-correction.h"
  40
  41 #include <cmath>
  42
  43 #include "gromacs/ewald/ewald-utils.h"
  44 #include "gromacs/math/functions.h"
  45 #include "gromacs/math/units.h"
  46 #include "gromacs/math/utilities.h"
  47 #include "gromacs/math/vec.h"
  48 #include "gromacs/mdtypes/commrec.h"
  49 #include "gromacs/mdtypes/forcerec.h"
  50 #include "gromacs/mdtypes/inputrec.h"
  51 #include "gromacs/mdtypes/md_enums.h"
  52 #include "gromacs/utility/fatalerror.h"
  53 #include "gromacs/utility/gmxassert.h"
  54
  55 #include "pme-internal.h"
  56
  57 /* There's nothing special to do here if just masses are perturbed,
  58  * but if either charge or type is perturbed then the implementation
  59  * requires that B states are defined for both charge and type, and
  60  * does not optimize for the cases where only one changes.
  61  *
  62  * The parameter vectors for B states are left undefined in atoms2md()
  63  * when either FEP is inactive, or when there are no mass/charge/type
  64  * perturbations. The parameter vectors for LJ-PME are likewise
  65  * undefined when LJ-PME is not active. This works because
  66  * bHaveChargeOrTypePerturbed handles the control flow. */
  67 void ewald_LRcorrection(int numAtomsLocal,
  68                         const t_commrec *cr,
  69                         int numThreads, int thread,
  70                         t_forcerec *fr,
  71                         const t_inputrec *ir,
  72                         real *chargeA, real *chargeB,
  73                         real *C6A, real *C6B,
  74                         real *sigmaA, real *sigmaB,
  75                         real *sigma3A, real *sigma3B,
  76                         gmx_bool bHaveChargeOrTypePerturbed,
  77                         gmx_bool calc_excl_corr,
  78                         const t_blocka *excl,
  79                         const rvec x[],
  80                         matrix box, rvec mu_tot[],
  81                         int ewald_geometry, real epsilon_surface,
  82                         rvec *f, tensor vir_q, tensor vir_lj,
  83                         real *Vcorr_q, real *Vcorr_lj,
  84                         real lambda_q, real lambda_lj,
  85                         real *dvdlambda_q, real *dvdlambda_lj)
  86 {
  87     int numAtomsToBeCorrected;
  88     if (calc_excl_corr)
  89     {
  90         /* We need to correct all exclusion pairs (cutoff-scheme = group) */
  91         numAtomsToBeCorrected = excl->nr;
  92
  93         GMX_RELEASE_ASSERT(numAtomsToBeCorrected >= numAtomsLocal, "We might need to do self-corrections");
  94     }
  95     else
  96     {
  97         /* We need to correct only self interactions */
  98         numAtomsToBeCorrected = numAtomsLocal;
  99     }
 100     int         start =  (numAtomsToBeCorrected* thread     )/numThreads;
 101     int         end   =  (numAtomsToBeCorrected*(thread + 1))/numThreads;
 102
 103     int         i, i1, i2, j, k, m, iv, jv, q;
 104     int        *AA;
 105     double      Vexcl_q, dvdl_excl_q, dvdl_excl_lj; /* Necessary for precision */
 106     double      Vexcl_lj;
 107     real        one_4pi_eps;
 108     real        v, vc, qiA, qiB, dr2, rinv;
 109     real        Vself_q[2], Vself_lj[2], Vdipole[2], rinv2, ewc_q = fr->ic->ewaldcoeff_q, ewcdr;
 110     real        ewc_lj = fr->ic->ewaldcoeff_lj, ewc_lj2 = ewc_lj * ewc_lj;
 111     real        c6Ai   = 0, c6Bi = 0, c6A = 0, c6B = 0, ewcdr2, ewcdr4, c6L = 0, rinv6;
 112     rvec        df, dx, mutot[2], dipcorrA, dipcorrB;
 113     tensor      dxdf_q = {{0}}, dxdf_lj = {{0}};
 114     real        L1_q, L1_lj, dipole_coeff, qqA, qqB, qqL, vr0_q, vr0_lj = 0;
 115     real        chargecorr[2] = { 0, 0 };
 116     gmx_bool    bMolPBC       = fr->bMolPBC;
 117     gmx_bool    bDoingLBRule  = (fr->ljpme_combination_rule == eljpmeLB);
 118     gmx_bool    bNeedLongRangeCorrection;
 119
 120     GMX_ASSERT(ir, "Invalid inputrec pointer");
 121     matrix          scaledBox;
 122     EwaldBoxZScaler boxScaler(*ir);
 123     boxScaler.scaleBox(box, scaledBox);
 124
 125     /* This routine can be made faster by using tables instead of analytical interactions
 126      * However, that requires a thorough verification that they are correct in all cases.
 127      */
 128
 129     bool vdwPme   = EVDW_PME(fr->ic->vdwtype);
 130
 131     one_4pi_eps   = ONE_4PI_EPS0/fr->ic->epsilon_r;
 132     vr0_q         = ewc_q*M_2_SQRTPI;
 133     if (vdwPme)
 134     {
 135         vr0_lj    = -gmx::power6(ewc_lj)/6.0;
 136     }
 137
 138     AA           = excl->a;
 139     Vexcl_q      = 0;
 140     Vexcl_lj     = 0;
 141     dvdl_excl_q  = 0;
 142     dvdl_excl_lj = 0;
 143     Vdipole[0]   = 0;
 144     Vdipole[1]   = 0;
 145     L1_q         = 1.0-lambda_q;
 146     L1_lj        = 1.0-lambda_lj;
 147     /* Note that we have to transform back to gromacs units, since
 148      * mu_tot contains the dipole in debye units (for output).
 149      */
 150     for (i = 0; (i < DIM); i++)
 151     {
 152         mutot[0][i] = mu_tot[0][i]*DEBYE2ENM;
 153         mutot[1][i] = mu_tot[1][i]*DEBYE2ENM;
 154         dipcorrA[i] = 0;
 155         dipcorrB[i] = 0;
 156     }
 157     dipole_coeff = 0;
 158
 159     real boxVolume = scaledBox[XX][XX]*scaledBox[YY][YY]*scaledBox[ZZ][ZZ];
 160     switch (ewald_geometry)
 161     {
 162         case eewg3D:
 163             if (epsilon_surface != 0)
 164             {
 165                 dipole_coeff =
 166                     2*M_PI*ONE_4PI_EPS0/((2*epsilon_surface + fr->ic->epsilon_r)*boxVolume);
 167                 for (i = 0; (i < DIM); i++)
 168                 {
 169                     dipcorrA[i] = 2*dipole_coeff*mutot[0][i];
 170                     dipcorrB[i] = 2*dipole_coeff*mutot[1][i];
 171                 }
 172             }
 173             break;
 174         case eewg3DC:
 175             dipole_coeff  = 2*M_PI*one_4pi_eps/boxVolume;
 176             dipcorrA[ZZ]  = 2*dipole_coeff*mutot[0][ZZ];
 177             dipcorrB[ZZ]  = 2*dipole_coeff*mutot[1][ZZ];
 178             for (int q = 0; q < (bHaveChargeOrTypePerturbed ? 2 : 1); q++)
 179             {
 180                 /* Avoid charge corrections with near-zero net charge */
 181                 if (fabs(fr->qsum[q]) > 1e-4)
 182                 {
 183                     chargecorr[q] = 2*dipole_coeff*fr->qsum[q];
 184                 }
 185             }
 186             break;
 187         default:
 188             gmx_incons("Unsupported Ewald geometry");
 189             break;
 190     }
 191     if (debug)
 192     {
 193         fprintf(debug, "dipcorr = %8.3f  %8.3f  %8.3f\n",
 194                 dipcorrA[XX], dipcorrA[YY], dipcorrA[ZZ]);
 195         fprintf(debug, "mutot   = %8.3f  %8.3f  %8.3f\n",
 196                 mutot[0][XX], mutot[0][YY], mutot[0][ZZ]);
 197     }
 198     bNeedLongRangeCorrection = (calc_excl_corr || dipole_coeff != 0);
 199     if (bNeedLongRangeCorrection && !bHaveChargeOrTypePerturbed)
 200     {
 201         for (i = start; (i < end); i++)
 202         {
 203             /* Initiate local variables (for this i-particle) to 0 */
 204             qiA = chargeA[i]*one_4pi_eps;
 205             if (vdwPme)
 206             {
 207                 c6Ai = C6A[i];
 208                 if (bDoingLBRule)
 209                 {
 210                     c6Ai *= sigma3A[i];
 211                 }
 212             }
 213             if (calc_excl_corr)
 214             {
 215                 i1  = excl->index[i];
 216                 i2  = excl->index[i+1];
 217
 218                 /* Loop over excluded neighbours */
 219                 for (j = i1; (j < i2); j++)
 220                 {
 221                     k = AA[j];
 222                     /*
 223                      * First we must test whether k <> i, and then,
 224                      * because the exclusions are all listed twice i->k
 225                      * and k->i we must select just one of the two.  As
 226                      * a minor optimization we only compute forces when
 227                      * the charges are non-zero.
 228                      */
 229                     if (k > i)
 230                     {
 231                         qqA = qiA*chargeA[k];
 232                         if (vdwPme)
 233                         {
 234                             c6A  = c6Ai * C6A[k];
 235                             if (bDoingLBRule)
 236                             {
 237                                 c6A *= gmx::power6(0.5*(sigmaA[i]+sigmaA[k]))*sigma3A[k];
 238                             }
 239                         }
 240                         if (qqA != 0.0 || c6A != 0.0)
 241                         {
 242                             rvec_sub(x[i], x[k], dx);
 243                             if (bMolPBC)
 244                             {
 245                                 /* Cheap pbc_dx, assume excluded pairs are at short distance. */
 246                                 for (m = DIM-1; (m >= 0); m--)
 247                                 {
 248                                     if (dx[m] > 0.5*box[m][m])
 249                                     {
 250                                         rvec_dec(dx, box[m]);
 251                                     }
 252                                     else if (dx[m] < -0.5*box[m][m])
 253                                     {
 254                                         rvec_inc(dx, box[m]);
 255                                     }
 256                                 }
 257                             }
 258                             dr2 = norm2(dx);
 259                             /* Distance between two excluded particles
 260                              * may be zero in the case of shells
 261                              */
 262                             if (dr2 != 0)
 263                             {
 264                                 rinv              = gmx::invsqrt(dr2);
 265                                 rinv2             = rinv*rinv;
 266                                 if (qqA != 0.0)
 267                                 {
 268                                     real dr, fscal;
 269
 270                                     dr       = 1.0/rinv;
 271                                     ewcdr    = ewc_q*dr;
 272                                     vc       = qqA*std::erf(ewcdr)*rinv;
 273                                     Vexcl_q += vc;
 274 #if GMX_DOUBLE
 275                                     /* Relative accuracy at R_ERF_R_INACC of 3e-10 */
 276 #define       R_ERF_R_INACC 0.006
 277 #else
 278                                     /* Relative accuracy at R_ERF_R_INACC of 2e-5 */
 279 #define       R_ERF_R_INACC 0.1
 280 #endif
 281                                     /* fscal is the scalar force pre-multiplied by rinv,
 282                                      * to normalise the relative position vector dx */
 283                                     if (ewcdr > R_ERF_R_INACC)
 284                                     {
 285                                         fscal = rinv2*(vc - qqA*ewc_q*M_2_SQRTPI*std::exp(-ewcdr*ewcdr));
 286                                     }
 287                                     else
 288                                     {
 289                                         /* Use a fourth order series expansion for small ewcdr */
 290                                         fscal = ewc_q*ewc_q*qqA*vr0_q*(2.0/3.0 - 0.4*ewcdr*ewcdr);
 291                                     }
 292
 293                                     /* The force vector is obtained by multiplication with
 294                                      * the relative position vector
 295                                      */
 296                                     svmul(fscal, dx, df);
 297                                     rvec_inc(f[k], df);
 298                                     rvec_dec(f[i], df);
 299                                     for (iv = 0; (iv < DIM); iv++)
 300                                     {
 301                                         for (jv = 0; (jv < DIM); jv++)
 302                                         {
 303                                             dxdf_q[iv][jv] += dx[iv]*df[jv];
 304                                         }
 305                                     }
 306                                 }
 307
 308                                 if (c6A != 0.0)
 309                                 {
 310                                     real fscal;
 311
 312                                     rinv6     = rinv2*rinv2*rinv2;
 313                                     ewcdr2    = ewc_lj2*dr2;
 314                                     ewcdr4    = ewcdr2*ewcdr2;
 315                                     /* We get the excluded long-range contribution from -C6*(1-g(r))
 316                                      * g(r) is also defined in the manual under LJ-PME
 317                                      */
 318                                     vc        = -c6A*rinv6*(1.0 - exp(-ewcdr2)*(1 + ewcdr2 + 0.5*ewcdr4));
 319                                     Vexcl_lj += vc;
 320                                     /* The force is the derivative of the potential vc.
 321                                      * fscal is the scalar force pre-multiplied by rinv,
 322                                      * to normalise the relative position vector dx */
 323                                     fscal     = 6.0*vc*rinv2 + c6A*rinv6*exp(-ewcdr2)*ewc_lj2*ewcdr4;
 324
 325                                     /* The force vector is obtained by multiplication with
 326                                      * the relative position vector
 327                                      */
 328                                     svmul(fscal, dx, df);
 329                                     rvec_inc(f[k], df);
 330                                     rvec_dec(f[i], df);
 331                                     for (iv = 0; (iv < DIM); iv++)
 332                                     {
 333                                         for (jv = 0; (jv < DIM); jv++)
 334                                         {
 335                                             dxdf_lj[iv][jv] += dx[iv]*df[jv];
 336                                         }
 337                                     }
 338                                 }
 339                             }
 340                             else
 341                             {
 342                                 Vexcl_q  += qqA*vr0_q;
 343                                 Vexcl_lj += c6A*vr0_lj;
 344                             }
 345                         }
 346                     }
 347                 }
 348             }
 349             /* Dipole correction on force */
 350             if (dipole_coeff != 0 && i < numAtomsLocal)
 351             {
 352                 for (j = 0; (j < DIM); j++)
 353                 {
 354                     f[i][j] -= dipcorrA[j]*chargeA[i];
 355                 }
 356                 if (chargecorr[0] != 0)
 357                 {
 358                     f[i][ZZ] += chargecorr[0]*chargeA[i]*x[i][ZZ];
 359                 }
 360             }
 361         }
 362     }
 363     else if (bNeedLongRangeCorrection)
 364     {
 365         for (i = start; (i < end); i++)
 366         {
 367             /* Initiate local variables (for this i-particle) to 0 */
 368             qiA = chargeA[i]*one_4pi_eps;
 369             qiB = chargeB[i]*one_4pi_eps;
 370             if (vdwPme)
 371             {
 372                 c6Ai = C6A[i];
 373                 c6Bi = C6B[i];
 374                 if (bDoingLBRule)
 375                 {
 376                     c6Ai *= sigma3A[i];
 377                     c6Bi *= sigma3B[i];
 378                 }
 379             }
 380             if (calc_excl_corr)
 381             {
 382                 i1  = excl->index[i];
 383                 i2  = excl->index[i+1];
 384
 385                 /* Loop over excluded neighbours */
 386                 for (j = i1; (j < i2); j++)
 387                 {
 388                     k = AA[j];
 389                     if (k > i)
 390                     {
 391                         qqA = qiA*chargeA[k];
 392                         qqB = qiB*chargeB[k];
 393                         if (vdwPme)
 394                         {
 395                             c6A = c6Ai*C6A[k];
 396                             c6B = c6Bi*C6B[k];
 397                             if (bDoingLBRule)
 398                             {
 399                                 c6A *= gmx::power6(0.5*(sigmaA[i]+sigmaA[k]))*sigma3A[k];
 400                                 c6B *= gmx::power6(0.5*(sigmaB[i]+sigmaB[k]))*sigma3B[k];
 401                             }
 402                         }
 403                         if (qqA != 0.0 || qqB != 0.0 || c6A != 0.0 || c6B != 0.0)
 404                         {
 405                             real fscal;
 406
 407                             qqL   = L1_q*qqA + lambda_q*qqB;
 408                             if (vdwPme)
 409                             {
 410                                 c6L = L1_lj*c6A + lambda_lj*c6B;
 411                             }
 412                             rvec_sub(x[i], x[k], dx);
 413                             if (bMolPBC)
 414                             {
 415                                 /* Cheap pbc_dx, assume excluded pairs are at short distance. */
 416                                 for (m = DIM-1; (m >= 0); m--)
 417                                 {
 418                                     if (dx[m] > 0.5*box[m][m])
 419                                     {
 420                                         rvec_dec(dx, box[m]);
 421                                     }
 422                                     else if (dx[m] < -0.5*box[m][m])
 423                                     {
 424                                         rvec_inc(dx, box[m]);
 425                                     }
 426                                 }
 427                             }
 428                             dr2 = norm2(dx);
 429                             if (dr2 != 0)
 430                             {
 431                                 rinv    = gmx::invsqrt(dr2);
 432                                 rinv2   = rinv*rinv;
 433                                 if (qqA != 0.0 || qqB != 0.0)
 434                                 {
 435                                     real dr;
 436
 437                                     dr           = 1.0/rinv;
 438                                     v            = std::erf(ewc_q*dr)*rinv;
 439                                     vc           = qqL*v;
 440                                     Vexcl_q     += vc;
 441                                     /* fscal is the scalar force pre-multiplied by rinv,
 442                                      * to normalise the relative position vector dx */
 443                                     fscal        = rinv2*(vc-qqL*ewc_q*M_2_SQRTPI*std::exp(-ewc_q*ewc_q*dr2));
 444                                     dvdl_excl_q += (qqB - qqA)*v;
 445
 446                                     /* The force vector is obtained by multiplication with
 447                                      * the relative position vector
 448                                      */
 449                                     svmul(fscal, dx, df);
 450                                     rvec_inc(f[k], df);
 451                                     rvec_dec(f[i], df);
 452                                     for (iv = 0; (iv < DIM); iv++)
 453                                     {
 454                                         for (jv = 0; (jv < DIM); jv++)
 455                                         {
 456                                             dxdf_q[iv][jv] += dx[iv]*df[jv];
 457                                         }
 458                                     }
 459                                 }
 460
 461                                 if ((c6A != 0.0 || c6B != 0.0) && vdwPme)
 462                                 {
 463                                     rinv6         = rinv2*rinv2*rinv2;
 464                                     ewcdr2        = ewc_lj2*dr2;
 465                                     ewcdr4        = ewcdr2*ewcdr2;
 466                                     v             = -rinv6*(1.0 - exp(-ewcdr2)*(1 + ewcdr2 + 0.5*ewcdr4));
 467                                     vc            = c6L*v;
 468                                     Vexcl_lj     += vc;
 469                                     /* fscal is the scalar force pre-multiplied by rinv,
 470                                      * to normalise the relative position vector dx */
 471                                     fscal         = 6.0*vc*rinv2 + c6L*rinv6*exp(-ewcdr2)*ewc_lj2*ewcdr4;
 472                                     dvdl_excl_lj += (c6B - c6A)*v;
 473
 474                                     /* The force vector is obtained by multiplication with
 475                                      * the relative position vector
 476                                      */
 477                                     svmul(fscal, dx, df);
 478                                     rvec_inc(f[k], df);
 479                                     rvec_dec(f[i], df);
 480                                     for (iv = 0; (iv < DIM); iv++)
 481                                     {
 482                                         for (jv = 0; (jv < DIM); jv++)
 483                                         {
 484                                             dxdf_lj[iv][jv] += dx[iv]*df[jv];
 485                                         }
 486                                     }
 487                                 }
 488                             }
 489                             else
 490                             {
 491                                 Vexcl_q      += qqL*vr0_q;
 492                                 dvdl_excl_q  += (qqB - qqA)*vr0_q;
 493                                 Vexcl_lj     += c6L*vr0_lj;
 494                                 dvdl_excl_lj += (c6B - c6A)*vr0_lj;
 495                             }
 496                         }
 497                     }
 498                 }
 499             }
 500             /* Dipole correction on force */
 501             if (dipole_coeff != 0 && i < numAtomsLocal)
 502             {
 503                 for (j = 0; (j < DIM); j++)
 504                 {
 505                     f[i][j] -= L1_q*dipcorrA[j]*chargeA[i]
 506                         + lambda_q*dipcorrB[j]*chargeB[i];
 507                 }
 508                 if (chargecorr[0] != 0 || chargecorr[1] != 0)
 509                 {
 510                     f[i][ZZ] += (L1_q*chargecorr[0]*chargeA[i]
 511                                  + lambda_q*chargecorr[1])*x[i][ZZ];
 512                 }
 513             }
 514         }
 515     }
 516     for (iv = 0; (iv < DIM); iv++)
 517     {
 518         for (jv = 0; (jv < DIM); jv++)
 519         {
 520             vir_q[iv][jv]  += 0.5*dxdf_q[iv][jv];
 521             vir_lj[iv][jv] += 0.5*dxdf_lj[iv][jv];
 522         }
 523     }
 524
 525     Vself_q[0]  = 0;
 526     Vself_q[1]  = 0;
 527     Vself_lj[0] = 0;
 528     Vself_lj[1] = 0;
 529
 530     /* Global corrections only on master process */
 531     if (MASTER(cr) && thread == 0)
 532     {
 533         for (q = 0; q < (bHaveChargeOrTypePerturbed ? 2 : 1); q++)
 534         {
 535             if (calc_excl_corr)
 536             {
 537                 /* Self-energy correction */
 538                 Vself_q[q] = ewc_q*one_4pi_eps*fr->q2sum[q]*M_1_SQRTPI;
 539                 if (vdwPme)
 540                 {
 541                     Vself_lj[q] =  fr->c6sum[q]*0.5*vr0_lj;
 542                 }
 543             }
 544
 545             /* Apply surface and charged surface dipole correction:
 546              * correction = dipole_coeff * ( (dipole)^2
 547              *              - qsum*sum_i q_i z_i^2 - qsum^2 * box_z^2 / 12 )
 548              */
 549             if (dipole_coeff != 0)
 550             {
 551                 if (ewald_geometry == eewg3D)
 552                 {
 553                     Vdipole[q] = dipole_coeff*iprod(mutot[q], mutot[q]);
 554                 }
 555                 else if (ewald_geometry == eewg3DC)
 556                 {
 557                     Vdipole[q] = dipole_coeff*mutot[q][ZZ]*mutot[q][ZZ];
 558
 559                     if (chargecorr[q] != 0)
 560                     {
 561                         /* Here we use a non thread-parallelized loop,
 562                          * because this is the only loop over atoms for
 563                          * energies and they need reduction (unlike forces).
 564                          * We could implement a reduction over threads,
 565                          * but this case is rarely used.
 566                          */
 567                         const real *qPtr   = (q == 0 ? chargeA : chargeB);
 568                         real        sumQZ2 = 0;
 569                         for (int i = 0; i < numAtomsLocal; i++)
 570                         {
 571                             sumQZ2 += qPtr[i]*x[i][ZZ]*x[i][ZZ];
 572                         }
 573                         Vdipole[q] -= dipole_coeff*fr->qsum[q]*(sumQZ2 + fr->qsum[q]*box[ZZ][ZZ]*box[ZZ][ZZ]/12);
 574                     }
 575                 }
 576             }
 577         }
 578     }
 579     if (!bHaveChargeOrTypePerturbed)
 580     {
 581         *Vcorr_q = Vdipole[0] - Vself_q[0] - Vexcl_q;
 582         if (vdwPme)
 583         {
 584             *Vcorr_lj = -Vself_lj[0] - Vexcl_lj;
 585         }
 586     }
 587     else
 588     {
 589         *Vcorr_q = L1_q*(Vdipole[0] - Vself_q[0])
 590             + lambda_q*(Vdipole[1] - Vself_q[1])
 591             - Vexcl_q;
 592         *dvdlambda_q += Vdipole[1] - Vself_q[1]
 593             - (Vdipole[0] - Vself_q[0]) - dvdl_excl_q;
 594         if (vdwPme)
 595         {
 596             *Vcorr_lj      = -(L1_lj*Vself_lj[0] + lambda_lj*Vself_lj[1]) - Vexcl_lj;
 597             *dvdlambda_lj += -Vself_lj[1] + Vself_lj[0] - dvdl_excl_lj;
 598         }
 599     }
 600
 601     if (debug)
 602     {
 603         fprintf(debug, "Long Range corrections for Ewald interactions:\n");
 604         fprintf(debug, "q2sum = %g, Vself_q=%g c6sum = %g, Vself_lj=%g\n",
 605                 L1_q*fr->q2sum[0]+lambda_q*fr->q2sum[1], L1_q*Vself_q[0]+lambda_q*Vself_q[1], L1_lj*fr->c6sum[0]+lambda_lj*fr->c6sum[1], L1_lj*Vself_lj[0]+lambda_lj*Vself_lj[1]);
 606         fprintf(debug, "Electrostatic Long Range correction: Vexcl=%g\n", Vexcl_q);
 607         fprintf(debug, "Lennard-Jones Long Range correction: Vexcl=%g\n", Vexcl_lj);
 608         if (MASTER(cr) && thread == 0)
 609         {
 610             if (epsilon_surface > 0 || ewald_geometry == eewg3DC)
 611             {
 612                 fprintf(debug, "Total dipole correction: Vdipole=%g\n",
 613                         L1_q*Vdipole[0]+lambda_q*Vdipole[1]);
 614             }
 615         }
 616     }
 617 }