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44 #include "gromacs/commandline/pargs.h"
47 #include "gromacs/utility/smalloc.h"
52 #include "gromacs/utility/futil.h"
59 #include "mtop_util.h"
63 #include "gromacs/linearalgebra/eigensolver.h"
64 #include "gromacs/linearalgebra/mtxio.h"
65 #include "gromacs/linearalgebra/sparsematrix.h"
67 static double cv_corr(double nu, double T)
69 double x = PLANCK*nu/(BOLTZ*T);
78 return BOLTZ*KILO*(ex*sqr(x)/sqr(ex-1) - 1);
82 static double u_corr(double nu, double T)
84 double x = PLANCK*nu/(BOLTZ*T);
93 return BOLTZ*T*(0.5*x - 1 + x/(ex-1));
97 static int get_nharm_mt(gmx_moltype_t *mt)
99 static int harm_func[] = { F_BONDS };
103 for (i = 0; (i < asize(harm_func)); i++)
106 nh += mt->ilist[ft].nr/(interaction_function[ft].nratoms+1);
111 static int get_nvsite_mt(gmx_moltype_t *mt)
113 static int vs_func[] = {
114 F_VSITE2, F_VSITE3, F_VSITE3FD, F_VSITE3FAD,
115 F_VSITE3OUT, F_VSITE4FD, F_VSITE4FDN, F_VSITEN
120 for (i = 0; (i < asize(vs_func)); i++)
123 nh += mt->ilist[ft].nr/(interaction_function[ft].nratoms+1);
128 static int get_nharm(gmx_mtop_t *mtop, int *nvsites)
134 for (j = 0; (j < mtop->nmolblock); j++)
136 mt = mtop->molblock[j].type;
137 nh += mtop->molblock[j].nmol * get_nharm_mt(&(mtop->moltype[mt]));
138 nv += mtop->molblock[j].nmol * get_nvsite_mt(&(mtop->moltype[mt]));
145 nma_full_hessian(real * hess,
158 natoms = top->atoms.nr;
160 /* divide elements hess[i][j] by sqrt(mas[i])*sqrt(mas[j]) when required */
164 for (i = 0; (i < natoms); i++)
166 for (j = 0; (j < DIM); j++)
168 for (k = 0; (k < natoms); k++)
170 mass_fac = gmx_invsqrt(top->atoms.atom[i].m*top->atoms.atom[k].m);
171 for (l = 0; (l < DIM); l++)
173 hess[(i*DIM+j)*ndim+k*DIM+l] *= mass_fac;
180 /* call diagonalization routine. */
182 fprintf(stderr, "\nDiagonalizing to find vectors %d through %d...\n", begin, end);
185 eigensolver(hess, ndim, begin-1, end-1, eigenvalues, eigenvectors);
187 /* And scale the output eigenvectors */
188 if (bM && eigenvectors != NULL)
190 for (i = 0; i < (end-begin+1); i++)
192 for (j = 0; j < natoms; j++)
194 mass_fac = gmx_invsqrt(top->atoms.atom[j].m);
195 for (k = 0; (k < DIM); k++)
197 eigenvectors[i*ndim+j*DIM+k] *= mass_fac;
207 nma_sparse_hessian(gmx_sparsematrix_t * sparse_hessian,
221 natoms = top->atoms.nr;
224 /* Cannot check symmetry since we only store half matrix */
225 /* divide elements hess[i][j] by sqrt(mas[i])*sqrt(mas[j]) when required */
229 for (iatom = 0; (iatom < natoms); iatom++)
231 for (j = 0; (j < DIM); j++)
234 for (k = 0; k < sparse_hessian->ndata[row]; k++)
236 col = sparse_hessian->data[row][k].col;
238 mass_fac = gmx_invsqrt(top->atoms.atom[iatom].m*top->atoms.atom[katom].m);
239 sparse_hessian->data[row][k].value *= mass_fac;
244 fprintf(stderr, "\nDiagonalizing to find eigenvectors 1 through %d...\n", neig);
247 sparse_eigensolver(sparse_hessian, neig, eigenvalues, eigenvectors, 10000000);
249 /* Scale output eigenvectors */
250 if (bM && eigenvectors != NULL)
252 for (i = 0; i < neig; i++)
254 for (j = 0; j < natoms; j++)
256 mass_fac = gmx_invsqrt(top->atoms.atom[j].m);
257 for (k = 0; (k < DIM); k++)
259 eigenvectors[i*ndim+j*DIM+k] *= mass_fac;
268 int gmx_nmeig(int argc, char *argv[])
270 const char *desc[] = {
271 "[THISMODULE] calculates the eigenvectors/values of a (Hessian) matrix,",
272 "which can be calculated with [gmx-mdrun].",
273 "The eigenvectors are written to a trajectory file ([TT]-v[tt]).",
274 "The structure is written first with t=0. The eigenvectors",
275 "are written as frames with the eigenvector number as timestamp.",
276 "The eigenvectors can be analyzed with [gmx-anaeig].",
277 "An ensemble of structures can be generated from the eigenvectors with",
278 "[gmx-nmens]. When mass weighting is used, the generated eigenvectors",
279 "will be scaled back to plain Cartesian coordinates before generating the",
280 "output. In this case, they will no longer be exactly orthogonal in the",
281 "standard Cartesian norm, but in the mass-weighted norm they would be.[PAR]",
282 "This program can be optionally used to compute quantum corrections to heat capacity",
283 "and enthalpy by providing an extra file argument [TT]-qcorr[tt]. See the GROMACS",
284 "manual, Chapter 1, for details. The result includes subtracting a harmonic",
285 "degree of freedom at the given temperature.",
286 "The total correction is printed on the terminal screen.",
287 "The recommended way of getting the corrections out is:[PAR]",
288 "[TT]gmx nmeig -s topol.tpr -f nm.mtx -first 7 -last 10000 -T 300 -qc [-constr][tt][PAR]",
289 "The [TT]-constr[tt] option should be used when bond constraints were used during the",
290 "simulation [BB]for all the covalent bonds[bb]. If this is not the case, ",
291 "you need to analyze the [TT]quant_corr.xvg[tt] file yourself.[PAR]",
292 "To make things more flexible, the program can also take virtual sites into account",
293 "when computing quantum corrections. When selecting [TT]-constr[tt] and",
294 "[TT]-qc[tt], the [TT]-begin[tt] and [TT]-end[tt] options will be set automatically as well.",
295 "Again, if you think you know it better, please check the [TT]eigenfreq.xvg[tt]",
299 static gmx_bool bM = TRUE, bCons = FALSE;
300 static int begin = 1, end = 50, maxspec = 4000;
301 static real T = 298.15, width = 1;
304 { "-m", FALSE, etBOOL, {&bM},
305 "Divide elements of Hessian by product of sqrt(mass) of involved "
306 "atoms prior to diagonalization. This should be used for 'Normal Modes' "
308 { "-first", FALSE, etINT, {&begin},
309 "First eigenvector to write away" },
310 { "-last", FALSE, etINT, {&end},
311 "Last eigenvector to write away" },
312 { "-maxspec", FALSE, etINT, {&maxspec},
313 "Highest frequency (1/cm) to consider in the spectrum" },
314 { "-T", FALSE, etREAL, {&T},
315 "Temperature for computing quantum heat capacity and enthalpy when using normal mode calculations to correct classical simulations" },
316 { "-constr", FALSE, etBOOL, {&bCons},
317 "If constraints were used in the simulation but not in the normal mode analysis (this is the recommended way of doing it) you will need to set this for computing the quantum corrections." },
318 { "-width", FALSE, etREAL, {&width},
319 "Width (sigma) of the gaussian peaks (1/cm) when generating a spectrum" }
321 FILE *out, *qc, *spec;
330 real rdum, mass_fac, qcvtot, qutot, qcv, qu;
331 int natoms, ndim, nrow, ncol, count, nharm, nvsite;
333 int i, j, k, l, d, gnx;
337 int version, generation;
338 real value, omega, nu;
339 real factor_gmx_to_omega2;
340 real factor_omega_to_wavenumber;
341 real *spectrum = NULL;
344 const char *qcleg[] = {
345 "Heat Capacity cV (J/mol K)",
346 "Enthalpy H (kJ/mol)"
348 real * full_hessian = NULL;
349 gmx_sparsematrix_t * sparse_hessian = NULL;
352 { efMTX, "-f", "hessian", ffREAD },
353 { efTPX, NULL, NULL, ffREAD },
354 { efXVG, "-of", "eigenfreq", ffWRITE },
355 { efXVG, "-ol", "eigenval", ffWRITE },
356 { efXVG, "-os", "spectrum", ffOPTWR },
357 { efXVG, "-qc", "quant_corr", ffOPTWR },
358 { efTRN, "-v", "eigenvec", ffWRITE }
360 #define NFILE asize(fnm)
362 if (!parse_common_args(&argc, argv, PCA_BE_NICE,
363 NFILE, fnm, asize(pa), pa, asize(desc), desc, 0, NULL, &oenv))
368 /* Read tpr file for volume and number of harmonic terms */
369 read_tpxheader(ftp2fn(efTPX, NFILE, fnm), &tpx, TRUE, &version, &generation);
370 snew(top_x, tpx.natoms);
372 read_tpx(ftp2fn(efTPX, NFILE, fnm), NULL, box, &natoms,
373 top_x, NULL, NULL, &mtop);
376 nharm = get_nharm(&mtop, &nvsite);
383 top = gmx_mtop_t_to_t_topology(&mtop);
388 if (opt2bSet("-qc", NFILE, fnm))
390 begin = 7+DIM*nvsite;
401 printf("Using begin = %d and end = %d\n", begin, end);
403 /*open Hessian matrix */
404 gmx_mtxio_read(ftp2fn(efMTX, NFILE, fnm), &nrow, &ncol, &full_hessian, &sparse_hessian);
406 /* Memory for eigenvalues and eigenvectors (begin..end) */
407 snew(eigenvalues, nrow);
408 snew(eigenvectors, nrow*(end-begin+1));
410 /* If the Hessian is in sparse format we can calculate max (ndim-1) eigenvectors,
411 * and they must start at the first one. If this is not valid we convert to full matrix
412 * storage, but warn the user that we might run out of memory...
414 if ((sparse_hessian != NULL) && (begin != 1 || end == ndim))
418 fprintf(stderr, "Cannot use sparse Hessian with first eigenvector != 1.\n");
420 else if (end == ndim)
422 fprintf(stderr, "Cannot use sparse Hessian to calculate all eigenvectors.\n");
425 fprintf(stderr, "Will try to allocate memory and convert to full matrix representation...\n");
427 snew(full_hessian, nrow*ncol);
428 for (i = 0; i < nrow*ncol; i++)
433 for (i = 0; i < sparse_hessian->nrow; i++)
435 for (j = 0; j < sparse_hessian->ndata[i]; j++)
437 k = sparse_hessian->data[i][j].col;
438 value = sparse_hessian->data[i][j].value;
439 full_hessian[i*ndim+k] = value;
440 full_hessian[k*ndim+i] = value;
443 gmx_sparsematrix_destroy(sparse_hessian);
444 sparse_hessian = NULL;
445 fprintf(stderr, "Converted sparse to full matrix storage.\n");
448 if (full_hessian != NULL)
450 /* Using full matrix storage */
451 nma_full_hessian(full_hessian, nrow, bM, &top, begin, end,
452 eigenvalues, eigenvectors);
456 /* Sparse memory storage, allocate memory for eigenvectors */
457 snew(eigenvectors, ncol*end);
458 nma_sparse_hessian(sparse_hessian, bM, &top, end, eigenvalues, eigenvectors);
461 /* check the output, first 6 eigenvalues should be reasonably small */
463 for (i = begin-1; (i < 6); i++)
465 if (fabs(eigenvalues[i]) > 1.0e-3)
472 fprintf(stderr, "\nOne of the lowest 6 eigenvalues has a non-zero value.\n");
473 fprintf(stderr, "This could mean that the reference structure was not\n");
474 fprintf(stderr, "properly energy minimized.\n");
477 /* now write the output */
478 fprintf (stderr, "Writing eigenvalues...\n");
479 out = xvgropen(opt2fn("-ol", NFILE, fnm),
480 "Eigenvalues", "Eigenvalue index", "Eigenvalue [Gromacs units]",
482 if (output_env_get_print_xvgr_codes(oenv))
486 fprintf(out, "@ subtitle \"mass weighted\"\n");
490 fprintf(out, "@ subtitle \"not mass weighted\"\n");
494 for (i = 0; i <= (end-begin); i++)
496 fprintf (out, "%6d %15g\n", begin+i, eigenvalues[i]);
501 if (opt2bSet("-qc", NFILE, fnm))
503 qc = xvgropen(opt2fn("-qc", NFILE, fnm), "Quantum Corrections", "Eigenvector index", "", oenv);
504 xvgr_legend(qc, asize(qcleg), qcleg, oenv);
511 printf("Writing eigenfrequencies - negative eigenvalues will be set to zero.\n");
513 out = xvgropen(opt2fn("-of", NFILE, fnm),
514 "Eigenfrequencies", "Eigenvector index", "Wavenumber [cm\\S-1\\N]",
516 if (output_env_get_print_xvgr_codes(oenv))
520 fprintf(out, "@ subtitle \"mass weighted\"\n");
524 fprintf(out, "@ subtitle \"not mass weighted\"\n");
529 if (opt2bSet("-os", NFILE, fnm) && (maxspec > 0))
531 snew(spectrum, maxspec);
532 spec = xvgropen(opt2fn("-os", NFILE, fnm),
533 "Vibrational spectrum based on harmonic approximation",
534 "\\f{12}w\\f{4} (cm\\S-1\\N)",
535 "Intensity [Gromacs units]",
537 for (i = 0; (i < maxspec); i++)
543 /* Gromacs units are kJ/(mol*nm*nm*amu),
544 * where amu is the atomic mass unit.
546 * For the eigenfrequencies we want to convert this to spectroscopic absorption
547 * wavenumbers given in cm^(-1), which is the frequency divided by the speed of
548 * light. Do this by first converting to omega^2 (units 1/s), take the square
549 * root, and finally divide by the speed of light (nm/ps in gromacs).
551 factor_gmx_to_omega2 = 1.0E21/(AVOGADRO*AMU);
552 factor_omega_to_wavenumber = 1.0E-5/(2.0*M_PI*SPEED_OF_LIGHT);
554 for (i = begin; (i <= end); i++)
556 value = eigenvalues[i-begin];
561 omega = sqrt(value*factor_gmx_to_omega2);
562 nu = 1e-12*omega/(2*M_PI);
563 value = omega*factor_omega_to_wavenumber;
564 fprintf (out, "%6d %15g\n", i, value);
567 wfac = eigenvalues[i-begin]/(width*sqrt(2*M_PI));
568 for (j = 0; (j < maxspec); j++)
570 spectrum[j] += wfac*exp(-sqr(j-value)/(2*sqr(width)));
575 qcv = cv_corr(nu, T);
582 fprintf (qc, "%6d %15g %15g\n", i, qcv, qu);
590 for (j = 0; (j < maxspec); j++)
592 fprintf(spec, "%10g %10g\n", 1.0*j, spectrum[j]);
598 printf("Quantum corrections for harmonic degrees of freedom\n");
599 printf("Use appropriate -first and -last options to get reliable results.\n");
600 printf("There were %d constraints and %d vsites in the simulation\n",
602 printf("Total correction to cV = %g J/mol K\n", qcvtot);
603 printf("Total correction to H = %g kJ/mol\n", qutot);
605 please_cite(stdout, "Caleman2011b");
607 /* Writing eigenvectors. Note that if mass scaling was used, the eigenvectors
608 * were scaled back from mass weighted cartesian to plain cartesian in the
609 * nma_full_hessian() or nma_sparse_hessian() routines. Mass scaled vectors
610 * will not be strictly orthogonal in plain cartesian scalar products.
612 write_eigenvectors(opt2fn("-v", NFILE, fnm), natoms, eigenvectors, FALSE, begin, end,
613 eWXR_NO, NULL, FALSE, top_x, bM, eigenvalues);