Wall clock time and date at job start Sat Apr 11 2020 06:10:45 AMSOL-version 7.1 by G. D. Hawkins, D. J. Giesen, G. C. Lynch, C. C. Chambers, I. Rossi, J. W. Storer, J. Li, J. D. Thompson, P. Winget, B. J. Lynch, D. Rinaldi, D. A. Liotard, C. J. Cramer, and D. G. Truhlar Copyright 2004 by Regents of the University of Minnesota. All rights reserved. Notice: recipients of this code are asked to comply with the user agreement in Section 1 of the documentation file. ******************************************************************************* * 1SCF - SCF CALCULATION WITHOUT GEOMETRY OPTIMIZATION * - USE EF ROUTINE FOR MINIMUM SEARCH (DEFAULT) * GEO-OK - OVERRIDE INTERATOMIC DISTANCE CHECK * TLIMIT= - A TIME OF 15. SECONDS REQUESTED * CHARGE - CHARGE ON SYSTEM= -1 * AM1 - THE AM1 HAMILTONIAN TO BE USED * DEV - DEVELOPER OPTIONS ARE ALLOWED * SM5.42R - SM5.42R CALCULATIONS WILL BE PERFORMED * - CHARGE MODEL 2 WILL BE USED (CM2A) * - THE SOLVENT IS USER-SPECIFIED * DIELEC - THE SOLVENT DIELECTRIC CONSTANT IS 2.06 * IOFR - THE SOLVENT INDEX OF REFRACTION IS 1.4345 * ALPHA - THE SOLVENT ALPHA IS 0.00 * BETA - THE SOLVENT BETA IS 0.00 * GAMMA - THE SOLVENT MACROSCOPIC SURFACE TENSION IS * 38.93 CAL MOL^-1 ANGSTROM^-2 * FACARB - THE FRACTION OF AROMATIC CARBONS IS 0.00 * FEHALO - THE FRACTION OF ELECTRONEGATIVE HALOGENS IS 0.00 ******************************************************************************* Atom NO. Chemical Bond length Bond angle Dihedral angle number (k) symbol (angstroms) (degrees) (degrees) (I) NA:I NB:NA:I NC:NB:NA:I NA NB NC 1 1 C 2 2 O 1.42901 * 1 3 3 C 1.42901 * 114.00288 * 2 1 4 4 H 1.08998 * 110.01584 * 331.39642 * 3 2 1 5 5 C 1.54267 * 110.06967 * 92.81042 * 3 2 1 6 6 C 1.54888 * 104.19319 * 142.91896 * 5 3 2 7 7 C 1.54888 * 102.74920 * 322.05804 * 6 5 3 8 8 H 1.09004 * 110.60091 * 279.20727 * 7 6 5 9 9 C 1.50704 * 110.48883 * 156.62261 * 7 6 5 10 10 O 1.21284 * 119.99904 * 245.22579 * 9 7 6 11 11 N 1.34774 * 119.99946 * 65.22258 * 9 7 6 12 12 C 1.46924 * 120.63097 * 180.02562 * 11 9 7 13 13 C 1.53201 * 108.77641 * 233.58621 * 12 11 9 14 14 C 1.53040 * 109.30918 * 305.36353 * 13 12 11 15 15 N 1.46498 * 109.45941 * 181.38687 * 14 13 12 16 16 C 1.36945 * 119.99843 * 299.96852 * 15 14 13 17 17 H 1.07998 * 119.99589 * 33.90054 * 16 15 14 18 18 C 1.38805 * 120.00250 * 213.90297 * 16 15 14 19 19 N 1.31620 * 120.00022 * 23.01315 * 18 16 15 20 20 Si 1.86801 * 120.00062 * 202.73474 * 18 16 15 21 21 H 1.48496 * 109.47314 * 270.27443 * 20 18 16 22 22 H 1.48506 * 109.46996 * 30.27641 * 20 18 16 23 23 H 1.48504 * 109.47092 * 150.27336 * 20 18 16 24 24 C 1.46495 * 120.00584 * 119.97495 * 15 14 13 25 25 C 1.53003 * 109.46782 * 272.45114 * 24 15 14 26 26 O 1.42901 * 109.47379 * 64.99574 * 25 24 15 27 27 C 1.53039 * 109.52946 * 61.36922 * 14 13 12 28 28 C 1.46925 * 120.63379 * 359.97438 * 11 9 7 29 29 C 1.53875 * 110.03340 * 210.00395 * 3 2 1 30 30 H 1.08996 * 109.47222 * 179.97438 * 1 2 3 31 31 H 1.09002 * 109.46562 * 300.00144 * 1 2 3 32 32 H 1.09002 * 109.46788 * 59.99360 * 1 2 3 33 33 H 1.08997 * 110.48666 * 261.59075 * 5 3 2 34 34 H 1.08993 * 110.48984 * 24.10977 * 5 3 2 35 35 H 1.08998 * 110.75924 * 203.74058 * 6 5 3 36 36 H 1.09008 * 110.75825 * 80.37029 * 6 5 3 37 37 H 1.08998 * 109.59363 * 113.79744 * 12 11 9 38 38 H 1.09002 * 109.58986 * 353.37083 * 12 11 9 39 39 H 1.08990 * 109.49796 * 185.41253 * 13 12 11 40 40 H 1.09002 * 109.49394 * 65.31237 * 13 12 11 41 41 H 1.09005 * 109.45826 * 301.35571 * 14 13 12 42 42 H 0.97003 * 120.00128 * 179.72490 * 19 18 16 43 43 H 1.09003 * 109.47044 * 32.44247 * 24 15 14 44 44 H 1.08991 * 109.47817 * 152.45144 * 24 15 14 45 45 H 1.08997 * 109.47325 * 184.99946 * 25 24 15 46 46 H 1.09000 * 109.47044 * 304.99849 * 25 24 15 47 47 H 0.96696 * 114.00113 * 179.97438 * 26 25 24 48 48 H 1.09006 * 109.49597 * 58.57909 * 27 14 13 49 49 H 1.08998 * 109.49818 * 178.67199 * 27 14 13 50 50 H 1.08998 * 109.59267 * 246.20091 * 28 11 9 51 51 H 1.09001 * 109.58602 * 6.48448 * 28 11 9 52 52 H 1.08998 * 110.03398 * 121.38361 * 29 3 2 53 53 H 1.09005 * 110.03273 * 359.94718 * 29 3 2 Note: An asterisk (*) indicates this parameter was or will be optimized. Cartesian coordinates (angstroms) NO. Atom X Y Z 1 6 0.0000 0.0000 0.0000 2 8 1.4290 0.0000 0.0000 3 6 2.0103 1.3054 0.0000 4 1 1.3407 2.0120 -0.4903 5 6 2.2906 1.7601 1.4473 6 6 3.6249 2.5403 1.3485 7 6 4.4265 1.7166 0.3103 8 1 4.8836 0.8464 0.7815 9 6 5.4790 2.5739 -0.3443 10 8 5.4074 2.8232 -1.5291 11 7 6.4997 3.0637 0.3869 12 6 7.5331 3.9014 -0.2369 13 6 8.9081 3.3016 0.0740 14 6 9.0592 3.1405 1.5884 15 7 10.3859 2.5980 1.8915 16 6 10.7579 1.3789 1.3906 17 1 10.4070 1.0646 0.4188 18 6 11.5857 0.5472 2.1320 19 7 11.6530 0.6815 3.4396 20 14 12.5984 -0.7677 1.2748 21 1 11.8120 -2.0248 1.1954 22 1 12.9431 -0.3119 -0.0959 23 1 13.8454 -1.0117 2.0435 24 6 11.3146 3.3594 2.7304 25 6 12.1278 4.3142 1.8540 26 8 11.2568 5.2876 1.2745 27 6 7.9854 2.1833 2.1107 28 6 6.5998 2.7710 1.8233 29 6 3.3684 1.2777 -0.7229 30 1 -0.3633 -1.0276 -0.0005 31 1 -0.3632 0.5139 0.8900 32 1 -0.3633 0.5139 -0.8900 33 1 1.4930 2.4121 1.8035 34 1 2.3987 0.8972 2.1041 35 1 4.1373 2.5528 2.3105 36 1 3.4537 3.5546 0.9878 37 1 7.4761 4.9127 0.1658 38 1 7.3810 3.9265 -1.3159 39 1 9.6875 3.9649 -0.3008 40 1 8.9969 2.3272 -0.4062 41 1 8.9454 4.1117 2.0701 42 1 12.2286 0.0977 3.9582 43 1 10.7520 3.9328 3.4672 44 1 11.9888 2.6726 3.2420 45 1 12.8792 4.8160 2.4636 46 1 12.6203 3.7499 1.0620 47 1 11.7055 5.9276 0.7053 48 1 8.0831 1.2194 1.6111 49 1 8.1081 2.0505 3.1856 50 1 6.4667 3.6902 2.3937 51 1 5.8301 2.0521 2.1041 52 1 3.3579 1.9709 -1.5640 53 1 3.5845 0.2683 -1.0729 RHF calculation, no. of doubly occupied orbitals= 66 REFERENCES FOR PARAMETERS IN GAS-PHASE HAMILTONIAN: H: (AM1): M.J.S. DEWAR ET AL, J. AM. CHEM. SOC. 107 3902-3909 (1985) C: (AM1): M.J.S. DEWAR ET AL, J. AM. CHEM. SOC. 107 3902-3909 (1985) N: (AM1): M.J.S. DEWAR ET AL, J. AM. CHEM. SOC. 107 3902-3909 (1985) O: (AM1): M.J.S. DEWAR ET AL, J. AM. CHEM. SOC. 107 3902-3909 (1985) Si: (AM1): M.J.S.DEWAR, C. JIE, ORGANOMETALLICS, 6, 1486-1490 (1987). REFERENCE FOR CHARGE MODEL 2: J. Li, J. Xing, C. J. Cramer, and D. G. Truhlar, J. Chem. Phys. 111 (1999) 885. REFERENCE FOR THE PARAMETERIZATION OF THE SM5.42R SOLVATION MODEL: J. Li, T. Zhu, G. D. Hawkins, P. Winget, D. A. Liotard, C. J. Cramer, and D. G. Truhlar, Theor. Chem. Acc. 103 (1999) 9-63 P. Winget, J. D. Thompson C. J. Cramer,and D. G. Truhlar, J. Phys. Chem. B. submitted. CHARGE=-1 AM1 1SCF TLIMIT=15 GEO-OK SM5.42R & SOLVNT=GENORG IOFR=1.4345 ALPHA=0.00 BETA=0.00 GAMMA=38.93 & DIELEC=2.06 FACARB=0.00 FEHALO=0.00 DEV ZINC001098413862.mol2 53 1SCF WAS SPECIFIED, SO GEOMETRY OPTIMIZATION WAS NOT USED SCF FIELD WAS ACHIEVED Wall clock time and date at job start Sat Apr 11 2020 06:10:45 Heat of formation + Delta-G solvation = -115.250157 kcal Electronic energy + Delta-G solvation = -31704.663810 eV Core-core repulsion = 27576.703929 eV Total energy + Delta-G solvation = -4127.959880 eV No. of doubly occupied orbitals = 66 Molecular weight (most abundant/longest-lived isotopes) = 340.220 amu Computer time = 2.84 seconds Orbital eigenvalues (eV) -40.38572 -38.75781 -37.51732 -36.21324 -35.79101 -34.65956 -32.10174 -30.79989 -30.30189 -29.05700 -28.61881 -27.57209 -26.30188 -24.91777 -23.43562 -22.65324 -21.68730 -20.80178 -20.37215 -19.62520 -18.56641 -17.57579 -16.80959 -16.58313 -16.19401 -15.99327 -15.54611 -15.12756 -14.92581 -14.73653 -14.42578 -14.12235 -13.84024 -13.59573 -13.57263 -13.40384 -13.06980 -13.00893 -12.53279 -12.49853 -12.17465 -11.94795 -11.80024 -11.65720 -11.47347 -11.42960 -11.22697 -11.14102 -10.97456 -10.87372 -10.72760 -10.69303 -10.60521 -10.43496 -10.18859 -9.91216 -9.84300 -9.73179 -9.48864 -9.34037 -9.13495 -8.48706 -8.27668 -6.59255 -5.81506 -3.32037 2.85180 3.27594 3.33960 3.42270 3.46034 3.59598 4.31047 4.37926 4.46762 4.62454 4.95796 5.06549 5.09744 5.11750 5.13426 5.22644 5.25859 5.27453 5.31938 5.38194 5.40769 5.43922 5.55877 5.62738 5.65345 5.70753 5.73749 5.86756 5.93211 5.94288 6.04749 6.09068 6.17305 6.18474 6.21711 6.28819 6.41223 6.48757 6.55887 6.69005 6.81225 6.94713 7.04262 7.04434 7.23448 7.28728 7.59149 7.72591 7.82640 8.31997 8.42718 8.48924 9.18867 9.83359 10.40922 11.19694 Molecular weight = 340.22amu Principal moments of inertia in cm(-1) A = 0.014195 B = 0.002895 C = 0.002639 Principal moments of inertia in units of 10**(-40)*gram-cm**2 A = 1972.004440 B = 9671.096305 C =10609.349553 Net atomic charges, atomic populations, and dipole contributions calculated with CM2 Atom NO. Type Charge No. of electrons 1 C 0.030 3.970 2 O -0.383 6.383 3 C 0.084 3.916 4 H 0.064 0.936 5 C -0.145 4.145 6 C -0.113 4.113 7 C -0.112 4.112 8 H 0.104 0.896 9 C 0.521 3.479 10 O -0.554 6.554 11 N -0.600 5.600 12 C 0.114 3.886 13 C -0.135 4.135 14 C 0.188 3.812 15 N -0.574 5.574 16 C -0.246 4.246 17 H 0.061 0.939 18 C 0.006 3.994 19 N -0.891 5.891 20 Si 0.892 3.108 21 H -0.286 1.286 22 H -0.280 1.280 23 H -0.290 1.290 24 C 0.147 3.853 25 C 0.055 3.945 26 O -0.568 6.568 27 C -0.139 4.139 28 C 0.104 3.896 29 C -0.109 4.109 30 H 0.083 0.917 31 H 0.039 0.961 32 H 0.040 0.960 33 H 0.068 0.932 34 H 0.081 0.919 35 H 0.082 0.918 36 H 0.073 0.927 37 H 0.060 0.940 38 H 0.081 0.919 39 H 0.073 0.927 40 H 0.060 0.940 41 H 0.052 0.948 42 H 0.254 0.746 43 H 0.027 0.973 44 H 0.111 0.889 45 H 0.021 0.979 46 H 0.040 0.960 47 H 0.355 0.645 48 H 0.069 0.931 49 H 0.070 0.930 50 H 0.063 0.937 51 H 0.080 0.920 52 H 0.091 0.909 53 H 0.081 0.919 For the charges calculated by CM2: Dipole moment (debyes) X Y Z Total from point charges -15.932 5.583 -1.960 16.996 Note: The Mulliken population analysis charges presented below were not used in the solvation calculation but are provided for completeness. The chosen solvation model uses CM2 partial charges for calculating solvation energies. Net atomic charges, atomic populations, and dipole contributions using Mulliken population analysis Atom NO. Type Charge No. of electrons 1 C -0.066 4.066 2 O -0.302 6.302 3 C 0.026 3.974 4 H 0.082 0.918 5 C -0.182 4.182 6 C -0.151 4.151 7 C -0.133 4.133 8 H 0.122 0.878 9 C 0.309 3.691 10 O -0.432 6.432 11 N -0.333 5.333 12 C -0.008 4.008 13 C -0.175 4.175 14 C 0.080 3.920 15 N -0.293 5.293 16 C -0.376 4.376 17 H 0.078 0.922 18 C -0.193 4.193 19 N -0.535 5.535 20 Si 0.721 3.279 21 H -0.213 1.213 22 H -0.205 1.205 23 H -0.216 1.216 24 C 0.020 3.980 25 C -0.025 4.025 26 O -0.371 6.371 27 C -0.179 4.179 28 C -0.020 4.020 29 C -0.147 4.147 30 H 0.102 0.898 31 H 0.058 0.942 32 H 0.058 0.942 33 H 0.087 0.913 34 H 0.100 0.900 35 H 0.101 0.899 36 H 0.091 0.909 37 H 0.079 0.921 38 H 0.100 0.900 39 H 0.092 0.908 40 H 0.079 0.921 41 H 0.070 0.930 42 H 0.064 0.936 43 H 0.046 0.954 44 H 0.129 0.871 45 H 0.039 0.961 46 H 0.058 0.942 47 H 0.199 0.801 48 H 0.088 0.912 49 H 0.089 0.911 50 H 0.081 0.919 51 H 0.098 0.902 52 H 0.110 0.890 53 H 0.100 0.900 Dipole moment (debyes) X Y Z Total from point charges -16.187 5.101 -2.095 17.100 hybrid contribution 1.022 -0.295 -0.558 1.201 sum -15.164 4.806 -2.653 16.128 Atomic orbital electron populations 1.22763 0.81496 1.02581 0.99779 1.87974 1.19313 1.27933 1.94956 1.22868 0.94963 0.84204 0.95361 0.91755 1.22890 0.97465 1.00534 0.97351 1.22555 0.95076 0.98695 0.98786 1.22073 0.94919 0.98930 0.97382 0.87760 1.20407 0.82134 0.79917 0.86637 1.90632 1.76506 1.60457 1.15644 1.48129 1.24601 1.50543 1.09982 1.21673 0.87518 0.92961 0.98673 1.22284 0.94149 1.01109 0.99915 1.20207 0.85465 0.94201 0.92093 1.43771 1.09322 1.17617 1.58561 1.18985 1.27157 0.93070 0.98356 0.92180 1.25032 1.02392 0.97283 0.94639 1.69960 1.39756 1.39792 1.03997 0.86473 0.80152 0.81980 0.79270 1.21337 1.20526 1.21589 1.21120 0.94020 0.91826 0.91040 1.23189 0.92817 0.89720 0.96768 1.86579 1.38462 1.44799 1.67300 1.22380 0.92458 1.01084 1.01965 1.22043 0.99715 1.00255 0.79939 1.22145 0.91114 1.03550 0.97876 0.89813 0.94187 0.94169 0.91345 0.90048 0.89928 0.90858 0.92144 0.90023 0.90821 0.92114 0.92954 0.93623 0.95449 0.87139 0.96086 0.94189 0.80072 0.91221 0.91120 0.91900 0.90191 0.89008 0.90041 Number of geometries 1 Number of calculations of the screened coulomb radii 1 The total number of SCF iterations 19. Note: The number of geometries may not correspond to the number of cycles due to rejected geometry changes. In the following table subtotal= G_P + SS G_CDS. Atom Chem. CM2 G_P Area Sigma k SS G_CDS Subtotal M number symbol chg. (kcal) (Ang**2) cal/(Ang**2) (kcal) (kcal) value 1 C 0.03 0.23 10.85 101.05 1.10 1.33 16 2 O -0.38 -4.25 10.26 -35.23 -0.36 -4.61 16 3 C 0.08 0.86 3.38 -25.61 -0.09 0.77 16 4 H 0.06 0.59 7.80 -51.93 -0.41 0.18 16 5 C -0.14 -1.31 6.56 -25.07 -0.16 -1.47 16 6 C -0.11 -1.13 5.56 -24.74 -0.14 -1.26 16 7 C -0.11 -1.39 2.29 -90.11 -0.21 -1.60 16 8 H 0.10 1.29 7.59 -51.93 -0.39 0.90 16 9 C 0.52 8.20 7.06 -10.98 -0.08 8.12 16 10 O -0.55 -10.37 14.83 5.55 0.08 -10.29 16 11 N -0.60 -9.32 2.97 -172.74 -0.51 -9.83 16 12 C 0.11 1.86 6.43 -3.71 -0.02 1.84 16 13 C -0.13 -2.52 5.30 -26.61 -0.14 -2.66 16 14 C 0.19 3.74 2.06 -67.89 -0.14 3.60 16 15 N -0.57 -13.36 2.37 -165.62 -0.39 -13.75 16 16 C -0.25 -6.35 8.27 -15.06 -0.12 -6.47 16 17 H 0.06 1.60 6.87 -52.49 -0.36 1.24 16 18 C 0.01 0.15 4.93 -17.43 -0.09 0.06 16 19 N -0.89 -24.38 11.34 55.49 0.63 -23.75 16 20 Si 0.89 21.10 29.61 -169.99 -5.03 16.07 16 21 H -0.29 -6.85 7.11 56.52 0.40 -6.45 16 22 H -0.28 -6.61 7.11 56.52 0.40 -6.21 16 23 H -0.29 -6.89 7.11 56.52 0.40 -6.49 16 24 C 0.15 3.30 5.65 -4.04 -0.02 3.28 16 25 C 0.05 1.05 7.39 37.16 0.27 1.33 16 26 O -0.57 -9.96 12.50 -35.23 -0.44 -10.40 16 27 C -0.14 -2.56 5.31 -26.59 -0.14 -2.70 16 28 C 0.10 1.47 5.55 -3.69 -0.02 1.45 16 29 C -0.11 -1.33 6.00 -25.61 -0.15 -1.48 16 30 H 0.08 0.54 8.14 -51.93 -0.42 0.12 16 31 H 0.04 0.26 8.14 -51.93 -0.42 -0.16 16 32 H 0.04 0.27 8.10 -51.93 -0.42 -0.15 16 33 H 0.07 0.52 8.14 -51.93 -0.42 0.10 16 34 H 0.08 0.76 8.08 -51.93 -0.42 0.34 16 35 H 0.08 0.75 6.29 -51.93 -0.33 0.42 16 36 H 0.07 0.74 8.05 -51.92 -0.42 0.32 16 37 H 0.06 0.91 8.14 -51.93 -0.42 0.49 16 38 H 0.08 1.39 7.01 -51.93 -0.36 1.03 16 39 H 0.07 1.42 7.58 -51.93 -0.39 1.02 16 40 H 0.06 1.28 7.03 -51.93 -0.37 0.91 16 41 H 0.05 1.05 7.80 -51.93 -0.40 0.64 16 42 H 0.25 6.76 8.31 -40.82 -0.34 6.42 16 43 H 0.03 0.61 7.97 -51.93 -0.41 0.19 16 44 H 0.11 2.79 5.33 -51.93 -0.28 2.52 16 45 H 0.02 0.36 8.14 -51.93 -0.42 -0.06 16 46 H 0.04 0.82 8.14 -51.93 -0.42 0.40 16 47 H 0.36 4.54 9.12 45.56 0.42 4.95 16 48 H 0.07 1.46 7.71 -51.93 -0.40 1.06 16 49 H 0.07 1.38 8.14 -51.93 -0.42 0.96 16 50 H 0.06 0.81 8.14 -51.93 -0.42 0.39 16 51 H 0.08 0.98 4.46 -51.93 -0.23 0.74 16 52 H 0.09 1.23 6.85 -51.93 -0.36 0.87 16 53 H 0.08 1.04 7.96 -51.93 -0.41 0.63 16 LS Contribution 402.82 15.07 6.07 6.07 Total: -1.00 -30.45 402.82 -8.58 -39.03 By element: Atomic # 1 Polarization: 15.80 SS G_CDS: -8.46 Total: 7.33 kcal Atomic # 6 Polarization: 4.29 SS G_CDS: -0.15 Total: 4.14 kcal Atomic # 7 Polarization: -47.05 SS G_CDS: -0.28 Total: -47.33 kcal Atomic # 8 Polarization: -24.59 SS G_CDS: -0.72 Total: -25.30 kcal Atomic # 14 Polarization: 21.10 SS G_CDS: -5.03 Total: 16.07 kcal Total LS contribution 6.07 Total: 6.07 kcal Total: -30.45 -8.58 -39.03 kcal The number of atoms in the molecule is 53 The average number of expansion shells was 16.00 The maximum number of expansion shells was 16 The minimum number of expansion shells was 16 **** NOTA BENE **** This is the net solvation energy for this exact molecular structure (nuclear and electronic)! The standard-state solvation energy should be obtained as the difference between the heat of formation plus delta-G solvation for the relaxed solvated system and that for the relaxed gas-phase system. ZINC001098413862.mol2 53 1SCF run This is a breakdown of the solvation energy calculated without geometric relaxation in solution: (1) E-EN(sol) electronic-nuclear energy of solute -76.222 kcal (2) G-P(sol) polarization free energy of solvation -30.451 kcal (3) G-ENP(sol) elect.-nuc.-pol. free energy of system -106.673 kcal (4) G-CDS(sol) cavity-dispersion-solvent structure free energy -8.577 kcal (5) G-P-CDS(sol) = G-P(sol) + G-CDS(sol) = (2) + (4) -39.028 kcal (6) G-S(sol) free energy of system = (1) + (5) -115.250 kcal 1SCF WAS SPECIFIED, SO GEOMETRY OPTIMIZATION WAS NOT USED Total computer time = 2.84 seconds