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

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