Wall clock time and date at job start Sat Apr 11 2020 06:10:52 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 N 2 2 C 1.31634 * 1 3 3 Si 1.86795 * 120.00163 * 2 1 4 4 H 1.48505 * 109.47125 * 269.99925 * 3 2 1 5 5 H 1.48499 * 109.47140 * 29.99534 * 3 2 1 6 6 H 1.48500 * 109.47238 * 149.99881 * 3 2 1 7 7 C 1.38797 * 119.99621 * 180.02562 * 2 1 3 8 8 H 1.08007 * 119.99539 * 180.02562 * 7 2 1 9 9 S 1.76198 * 120.00493 * 359.97438 * 7 2 1 10 10 C 1.80997 * 100.00145 * 180.02562 * 9 7 2 11 11 C 1.50702 * 109.46981 * 180.02562 * 10 9 7 12 12 O 1.21281 * 120.00144 * 5.06580 * 11 10 9 13 13 N 1.34772 * 119.99866 * 185.06708 * 11 10 9 14 14 C 1.46969 * 120.36243 * 175.05381 * 13 11 10 15 15 C 1.52330 * 109.10821 * 68.38641 * 14 13 11 16 16 C 1.53795 * 109.16032 * 72.70077 * 15 14 13 17 17 C 1.52452 * 109.40771 * 282.16221 * 16 15 14 18 18 C 1.53946 * 110.71937 * 113.73624 * 17 16 15 19 19 C 1.52880 * 109.73362 * 315.61270 * 18 17 16 20 20 H 1.09004 * 109.48154 * 47.11190 * 19 18 17 21 21 N 1.46904 * 109.48335 * 167.14382 * 19 18 17 22 22 C 1.46897 * 110.99778 * 204.97164 * 21 19 18 23 23 C 1.52999 * 109.47068 * 179.97438 * 22 21 19 24 24 C 1.53776 * 113.61405 * 274.13539 * 23 22 21 25 25 C 1.53955 * 87.02040 * 220.04491 * 24 23 22 26 26 C 1.53782 * 87.11225 * 25.36217 * 25 24 23 27 27 C 1.45337 * 120.36708 * 355.08132 * 13 11 10 28 28 H 0.96998 * 119.99556 * 0.02562 * 1 2 3 29 29 H 1.08996 * 109.47239 * 60.00364 * 10 9 7 30 30 H 1.08999 * 109.47101 * 300.00184 * 10 9 7 31 31 H 1.09001 * 109.53048 * 188.27567 * 14 13 11 32 32 H 1.09001 * 109.53213 * 308.49161 * 14 13 11 33 33 H 1.09007 * 109.52337 * 192.60616 * 15 14 13 34 34 H 1.09002 * 109.52509 * 312.79077 * 15 14 13 35 35 H 1.08997 * 109.48567 * 42.14016 * 16 15 14 36 36 H 1.09003 * 109.48433 * 162.18412 * 16 15 14 37 37 H 1.08998 * 109.22535 * 234.05612 * 17 16 15 38 38 H 1.09000 * 109.22122 * 353.44926 * 17 16 15 39 39 H 1.09000 * 109.41263 * 195.53808 * 18 17 16 40 40 H 1.08999 * 109.43647 * 75.70062 * 18 17 16 41 41 H 1.00895 * 110.99748 * 81.01408 * 21 19 18 42 42 H 1.09001 * 109.46984 * 299.99383 * 22 21 19 43 43 H 1.08999 * 109.47664 * 60.00137 * 22 21 19 44 44 H 1.09004 * 112.84862 * 45.32951 * 23 22 21 45 45 H 1.08999 * 113.61642 * 334.56410 * 24 23 22 46 46 H 1.09001 * 113.61620 * 105.46967 * 24 23 22 47 47 H 1.08996 * 113.54076 * 270.81374 * 25 24 23 48 48 H 1.09001 * 113.74288 * 139.93987 * 25 24 23 49 49 H 1.08993 * 113.61762 * 220.09111 * 26 25 24 50 50 H 1.08993 * 113.61303 * 89.18211 * 26 25 24 51 51 H 1.08994 * 109.68260 * 103.59339 * 27 13 11 52 52 H 1.08996 * 109.70598 * 343.06298 * 27 13 11 Note: An asterisk (*) indicates this parameter was or will be optimized. Cartesian coordinates (angstroms) NO. Atom X Y Z 1 7 0.0000 0.0000 0.0000 2 6 1.3163 0.0000 0.0000 3 14 2.2504 1.6177 0.0000 4 1 2.4979 2.0463 -1.4001 5 1 1.4478 2.6526 0.6999 6 1 3.5479 1.4401 0.7001 7 6 2.0102 -1.2021 -0.0005 8 1 3.0903 -1.2020 -0.0001 9 16 1.1293 -2.7280 -0.0005 10 6 2.5158 -3.8914 -0.0005 11 6 1.9873 -5.3027 -0.0012 12 8 0.7949 -5.5037 -0.0943 13 7 2.8397 -6.3415 0.1018 14 6 2.3275 -7.7148 0.2111 15 6 1.6787 -8.1115 -1.1087 16 6 2.7761 -8.3445 -2.1607 17 6 3.2795 -7.0002 -2.6740 18 6 4.7446 -6.7730 -2.2597 19 6 4.9342 -7.1685 -0.7952 20 1 4.4720 -8.1397 -0.6181 21 7 6.3692 -7.2458 -0.4903 22 6 6.6193 -8.1504 0.6397 23 6 8.1212 -8.2054 0.9263 24 6 8.8736 -9.2405 0.0736 25 6 9.6860 -9.5730 1.3383 26 6 8.4839 -9.0627 2.1504 27 6 4.2755 -6.1161 0.1066 28 1 -0.4849 0.8401 -0.0004 29 1 3.1244 -3.7314 0.8894 30 1 3.1244 -3.7313 -0.8905 31 1 3.1509 -8.3943 0.4313 32 1 1.5882 -7.7654 1.0105 33 1 1.1050 -9.0282 -0.9716 34 1 1.0165 -7.3131 -1.4437 35 1 3.6022 -8.8935 -1.7089 36 1 2.3674 -8.9206 -2.9910 37 1 3.2068 -6.9811 -3.7614 38 1 2.6619 -6.2036 -2.2591 39 1 4.9980 -5.7205 -2.3868 40 1 5.3972 -7.3805 -2.8867 41 1 6.7506 -6.3291 -0.3111 42 1 6.0940 -7.7839 1.5216 43 1 6.2603 -9.1494 0.3919 44 1 8.5878 -7.2202 0.9295 45 1 8.2455 -10.0622 -0.2705 46 1 9.4690 -8.7984 -0.7252 47 1 10.5815 -8.9624 1.4535 48 1 9.8801 -10.6377 1.4679 49 1 8.7651 -8.4773 3.0257 50 1 7.7491 -9.8357 2.3751 51 1 4.6587 -6.2117 1.1224 52 1 4.4921 -5.1184 -0.2751 RHF calculation, no. of doubly occupied orbitals= 63 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). S: (AM1): M.J.S. DEWAR, Y.-C. YUAN, INORGANIC CHEM., 29, 589 (1990) 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 ZINC001479683967.mol2 52 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 06:10:52 Heat of formation + Delta-G solvation = -18.928355 kcal Electronic energy + Delta-G solvation = -28540.209450 eV Core-core repulsion = 24859.179267 eV Total energy + Delta-G solvation = -3681.030183 eV No. of doubly occupied orbitals = 63 Molecular weight (most abundant/longest-lived isotopes) = 340.193 amu Computer time = 0.81 seconds Orbital eigenvalues (eV) -40.54401 -39.24677 -37.73552 -35.36863 -34.20006 -32.43787 -32.21440 -29.70136 -28.13347 -26.51558 -26.13475 -25.81352 -25.44043 -23.17278 -22.24724 -22.17630 -20.06539 -19.52057 -18.87480 -17.69104 -16.65967 -16.62998 -16.16204 -15.96634 -15.23137 -14.95887 -14.81271 -14.68945 -14.36425 -14.23383 -13.98188 -13.85038 -13.49433 -13.18956 -13.01903 -12.82406 -12.75285 -12.51171 -12.20996 -12.09895 -11.90325 -11.75834 -11.60322 -11.43481 -11.09942 -11.06701 -11.03025 -10.88356 -10.77091 -10.75569 -10.56784 -10.52422 -10.44799 -10.21796 -9.81849 -9.31523 -9.07415 -8.86461 -8.24005 -8.23710 -6.50930 -6.22542 -3.93050 2.92520 3.05006 3.21433 3.25078 3.29332 3.57251 3.83558 4.19410 4.31024 4.37740 4.40904 4.49798 4.60204 4.72612 4.80810 4.91628 4.97218 5.02315 5.08390 5.12172 5.12607 5.15182 5.28106 5.35153 5.40851 5.41836 5.43253 5.45855 5.55673 5.56727 5.59441 5.62771 5.66334 5.71437 5.73910 5.83859 5.86221 5.95805 5.99049 6.04319 6.09982 6.17746 6.18377 6.20003 6.33125 6.42962 6.71453 6.79831 7.10731 7.57483 7.59343 8.34126 8.57442 9.22778 10.84863 Molecular weight = 340.19amu Principal moments of inertia in cm(-1) A = 0.011586 B = 0.002807 C = 0.002438 Principal moments of inertia in units of 10**(-40)*gram-cm**2 A = 2416.115215 B = 9972.470969 C =11480.168442 Net atomic charges, atomic populations, and dipole contributions calculated with CM2 Atom NO. Type Charge No. of electrons 1 N -0.867 5.867 2 C 0.073 3.927 3 Si 0.918 3.082 4 H -0.277 1.277 5 H -0.282 1.282 6 H -0.272 1.272 7 C -0.534 4.534 8 H 0.072 0.928 9 S -0.060 6.060 10 C -0.151 4.151 11 C 0.535 3.465 12 O -0.512 6.512 13 N -0.611 5.611 14 C 0.122 3.878 15 C -0.143 4.143 16 C -0.120 4.120 17 C -0.123 4.123 18 C -0.103 4.103 19 C 0.062 3.938 20 H 0.097 0.903 21 N -0.678 5.678 22 C 0.066 3.934 23 C -0.107 4.107 24 C -0.125 4.125 25 C -0.146 4.146 26 C -0.138 4.138 27 C 0.081 3.919 28 H 0.268 0.732 29 H 0.085 0.915 30 H 0.088 0.912 31 H 0.075 0.925 32 H 0.069 0.931 33 H 0.066 0.934 34 H 0.086 0.914 35 H 0.065 0.935 36 H 0.058 0.942 37 H 0.058 0.942 38 H 0.069 0.931 39 H 0.061 0.939 40 H 0.069 0.931 41 H 0.341 0.659 42 H 0.032 0.968 43 H 0.071 0.929 44 H 0.089 0.911 45 H 0.079 0.921 46 H 0.066 0.934 47 H 0.077 0.923 48 H 0.065 0.935 49 H 0.065 0.935 50 H 0.080 0.920 51 H 0.057 0.943 52 H 0.088 0.912 For the charges calculated by CM2: Dipole moment (debyes) X Y Z Total from point charges 16.865 -20.851 0.111 26.818 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 N -0.503 5.503 2 C -0.136 4.136 3 Si 0.744 3.256 4 H -0.202 1.202 5 H -0.207 1.207 6 H -0.197 1.197 7 C -0.683 4.683 8 H 0.090 0.910 9 S 0.167 5.833 10 C -0.301 4.301 11 C 0.323 3.677 12 O -0.386 6.386 13 N -0.348 5.348 14 C -0.001 4.001 15 C -0.182 4.182 16 C -0.157 4.157 17 C -0.161 4.161 18 C -0.141 4.141 19 C -0.048 4.048 20 H 0.114 0.886 21 N -0.308 5.308 22 C -0.063 4.063 23 C -0.126 4.126 24 C -0.163 4.163 25 C -0.184 4.184 26 C -0.176 4.176 27 C -0.045 4.045 28 H 0.078 0.922 29 H 0.103 0.897 30 H 0.106 0.894 31 H 0.093 0.907 32 H 0.087 0.913 33 H 0.085 0.915 34 H 0.105 0.895 35 H 0.083 0.917 36 H 0.077 0.923 37 H 0.077 0.923 38 H 0.087 0.913 39 H 0.080 0.920 40 H 0.088 0.912 41 H 0.159 0.841 42 H 0.050 0.950 43 H 0.090 0.910 44 H 0.107 0.893 45 H 0.098 0.902 46 H 0.085 0.915 47 H 0.096 0.904 48 H 0.083 0.917 49 H 0.084 0.916 50 H 0.098 0.902 51 H 0.075 0.925 52 H 0.106 0.894 Dipole moment (debyes) X Y Z Total from point charges 15.050 -21.522 -0.408 26.265 hybrid contribution 1.765 1.923 0.823 2.737 sum 16.815 -19.599 0.415 25.827 Atomic orbital electron populations 1.70020 1.05939 1.27441 1.46858 1.24989 0.95028 0.99012 0.94551 0.86177 0.79410 0.81603 0.78371 1.20246 1.20745 1.19709 1.22846 0.94838 0.91646 1.58938 0.91025 1.85385 1.04953 0.96321 1.96676 1.23567 1.06436 0.95685 1.04449 1.20242 0.86171 0.86007 0.75292 1.90685 1.15409 1.85259 1.47246 1.47702 1.05728 1.06364 1.74985 1.21409 0.98292 0.82393 0.97989 1.22119 0.98378 1.02348 0.95328 1.21771 0.98132 0.97338 0.98506 1.21738 0.96038 0.98016 1.00350 1.21678 0.96391 1.01534 0.94490 1.22431 0.87295 0.99538 0.95574 0.88563 1.60652 1.13529 1.15479 1.41172 1.22033 0.95210 0.97300 0.91741 1.22528 0.94829 0.98748 0.96485 1.22879 0.98421 0.98630 0.96358 1.22871 0.97284 1.01041 0.97185 1.22926 0.98228 0.99520 0.96887 1.22334 0.81439 1.01191 0.99524 0.92188 0.89696 0.89373 0.90716 0.91290 0.91491 0.89546 0.91685 0.92333 0.92305 0.91276 0.92008 0.91190 0.84052 0.95018 0.91042 0.89265 0.90249 0.91521 0.90396 0.91668 0.91590 0.90162 0.92516 0.89408 Number of geometries 1 Number of calculations of the screened coulomb radii 1 The total number of SCF iterations 13. 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 N -0.87 -26.15 13.22 55.49 0.73 -25.42 16 2 C 0.07 2.10 5.49 -17.43 -0.10 2.00 16 3 Si 0.92 21.39 29.55 -169.99 -5.02 16.37 16 4 H -0.28 -6.32 7.11 56.52 0.40 -5.92 16 5 H -0.28 -6.47 7.11 56.52 0.40 -6.07 16 6 H -0.27 -6.15 7.11 56.52 0.40 -5.75 16 7 C -0.53 -15.19 9.50 30.94 0.29 -14.89 16 8 H 0.07 1.93 7.80 -52.48 -0.41 1.52 16 9 S -0.06 -1.63 20.58 -107.50 -2.21 -3.84 16 10 C -0.15 -3.06 4.56 36.01 0.16 -2.90 16 11 C 0.54 9.97 6.23 -10.99 -0.07 9.90 16 12 O -0.51 -11.39 14.44 5.56 0.08 -11.31 16 13 N -0.61 -8.38 1.68 -174.36 -0.29 -8.68 16 14 C 0.12 1.44 5.20 -4.13 -0.02 1.42 16 15 C -0.14 -1.70 5.54 -26.66 -0.15 -1.85 16 16 C -0.12 -1.23 5.49 -26.60 -0.15 -1.37 16 17 C -0.12 -1.42 5.40 -26.52 -0.14 -1.57 16 18 C -0.10 -1.04 5.35 -26.30 -0.14 -1.19 16 19 C 0.06 0.56 1.99 -67.54 -0.13 0.43 16 20 H 0.10 0.88 3.01 -51.93 -0.16 0.73 16 21 N -0.68 -5.47 6.25 -106.54 -0.67 -6.14 16 22 C 0.07 0.48 5.29 -3.83 -0.02 0.46 16 23 C -0.11 -0.72 3.89 -89.81 -0.35 -1.07 16 24 C -0.13 -0.83 7.65 -25.83 -0.20 -1.03 16 25 C -0.15 -0.88 8.09 -25.83 -0.21 -1.09 16 26 C -0.14 -0.85 7.65 -25.92 -0.20 -1.05 16 27 C 0.08 0.89 5.12 -4.44 -0.02 0.87 16 28 H 0.27 7.52 8.31 -40.82 -0.34 7.18 16 29 H 0.08 1.62 8.04 -51.92 -0.42 1.21 16 30 H 0.09 1.68 7.59 -51.92 -0.39 1.28 16 31 H 0.07 0.69 6.07 -51.93 -0.32 0.38 16 32 H 0.07 0.89 8.13 -51.93 -0.42 0.47 16 33 H 0.07 0.69 8.14 -51.93 -0.42 0.26 16 34 H 0.09 1.34 6.03 -51.93 -0.31 1.02 16 35 H 0.06 0.59 5.47 -51.93 -0.28 0.31 16 36 H 0.06 0.56 8.14 -51.93 -0.42 0.14 16 37 H 0.06 0.66 8.14 -51.93 -0.42 0.23 16 38 H 0.07 1.01 5.38 -51.93 -0.28 0.73 16 39 H 0.06 0.67 7.87 -51.93 -0.41 0.26 16 40 H 0.07 0.69 8.14 -51.93 -0.42 0.27 16 41 H 0.34 2.65 8.48 -39.29 -0.33 2.32 16 42 H 0.03 0.25 7.33 -51.93 -0.38 -0.14 16 43 H 0.07 0.53 7.79 -51.93 -0.40 0.13 16 44 H 0.09 0.62 8.14 -51.93 -0.42 0.19 16 45 H 0.08 0.54 7.92 -51.93 -0.41 0.13 16 46 H 0.07 0.47 8.14 -51.93 -0.42 0.04 16 47 H 0.08 0.45 8.14 -51.93 -0.42 0.03 16 48 H 0.06 0.37 8.14 -51.93 -0.42 -0.06 16 49 H 0.07 0.40 8.14 -51.93 -0.42 -0.02 16 50 H 0.08 0.48 8.10 -51.93 -0.42 0.06 16 51 H 0.06 0.58 7.26 -51.93 -0.38 0.21 16 52 H 0.09 1.03 5.89 -51.93 -0.31 0.72 16 LS Contribution 399.23 15.07 6.02 6.02 Total: -1.00 -32.28 399.23 -11.77 -44.06 By element: Atomic # 1 Polarization: 10.84 SS G_CDS: -8.97 Total: 1.87 kcal Atomic # 6 Polarization: -11.49 SS G_CDS: -1.44 Total: -12.92 kcal Atomic # 7 Polarization: -40.01 SS G_CDS: -0.23 Total: -40.23 kcal Atomic # 8 Polarization: -11.39 SS G_CDS: 0.08 Total: -11.31 kcal Atomic # 14 Polarization: 21.39 SS G_CDS: -5.02 Total: 16.37 kcal Atomic # 16 Polarization: -1.63 SS G_CDS: -2.21 Total: -3.84 kcal Total LS contribution 6.02 Total: 6.02 kcal Total: -32.28 -11.77 -44.06 kcal The number of atoms in the molecule is 52 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. ZINC001479683967.mol2 52 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 25.128 kcal (2) G-P(sol) polarization free energy of solvation -32.282 kcal (3) G-ENP(sol) elect.-nuc.-pol. free energy of system -7.154 kcal (4) G-CDS(sol) cavity-dispersion-solvent structure free energy -11.774 kcal (5) G-P-CDS(sol) = G-P(sol) + G-CDS(sol) = (2) + (4) -44.056 kcal (6) G-S(sol) free energy of system = (1) + (5) -18.928 kcal 1SCF WAS SPECIFIED, SO GEOMETRY OPTIMIZATION WAS NOT USED Total computer time = 0.81 seconds