Wall clock time and date at job start Wed Apr 1 2020 03:56:06 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 1.31624 * 1 3 3 Si 1.86801 * 119.99822 * 2 1 4 4 H 1.48504 * 109.46975 * 354.39737 * 3 2 1 5 5 H 1.48497 * 109.47235 * 114.39310 * 3 2 1 6 6 H 1.48497 * 109.47169 * 234.39730 * 3 2 1 7 7 C 1.38811 * 119.99979 * 180.02562 * 2 1 3 8 8 H 1.07997 * 120.00028 * 9.18831 * 7 2 1 9 9 N 1.36934 * 119.99682 * 189.18324 * 7 2 1 10 10 C 1.47431 * 125.64876 * 29.90271 * 9 7 2 11 11 C 1.54911 * 104.83240 * 155.83386 * 10 9 7 12 12 C 1.55159 * 101.58096 * 37.00934 * 11 10 9 13 13 C 1.47024 * 125.65093 * 209.59382 * 9 7 2 14 14 H 1.09004 * 109.88214 * 300.51867 * 13 9 7 15 15 C 1.53004 * 109.88156 * 61.67995 * 13 9 7 16 16 C 1.53003 * 109.46737 * 292.65206 * 15 13 9 17 17 C 1.53005 * 109.46627 * 184.53373 * 16 15 13 18 18 N 1.46502 * 109.47006 * 179.97438 * 17 16 15 19 19 C 1.34772 * 120.00266 * 179.97438 * 18 17 16 20 20 O 1.21285 * 119.99770 * 0.02562 * 19 18 17 21 21 C 1.50704 * 120.00179 * 180.02562 * 19 18 17 22 22 H 1.08997 * 109.43300 * 60.09784 * 21 19 18 23 23 C 1.53119 * 109.43051 * 180.02562 * 21 19 18 24 24 C 1.53490 * 109.30702 * 189.98480 * 23 21 19 25 25 C 1.50714 * 108.05853 * 311.29203 * 24 23 21 26 26 C 1.33861 * 128.68393 * 195.74733 * 25 24 23 27 27 N 1.34423 * 107.79503 * 179.90652 * 26 25 24 28 28 C 1.30784 * 109.32600 * 0.02562 * 27 26 25 29 29 N 1.34406 * 108.55224 * 0.06278 * 28 27 26 30 30 C 1.46470 * 128.44573 * 179.80247 * 29 28 27 31 31 H 0.96994 * 119.99730 * 174.91017 * 1 2 3 32 32 H 1.08993 * 110.36795 * 274.66899 * 10 9 7 33 33 H 1.08996 * 110.36542 * 37.00080 * 10 9 7 34 34 H 1.08993 * 111.00805 * 155.08386 * 11 10 9 35 35 H 1.09004 * 111.00183 * 278.90074 * 11 10 9 36 36 H 1.09000 * 110.71769 * 82.86341 * 12 11 10 37 37 H 1.09000 * 110.71822 * 205.95922 * 12 11 10 38 38 H 1.08998 * 109.46886 * 52.64406 * 15 13 9 39 39 H 1.08994 * 109.47180 * 172.64920 * 15 13 9 40 40 H 1.08996 * 109.47140 * 304.52718 * 16 15 13 41 41 H 1.08998 * 109.47552 * 64.53355 * 16 15 13 42 42 H 1.08996 * 109.46825 * 299.99537 * 17 16 15 43 43 H 1.08992 * 109.47443 * 60.00105 * 17 16 15 44 44 H 0.96999 * 120.00027 * 0.02562 * 18 17 16 45 45 H 1.09008 * 109.49519 * 309.93268 * 23 21 19 46 46 H 1.08995 * 109.50471 * 70.03022 * 23 21 19 47 47 H 1.09003 * 109.74556 * 70.93196 * 24 23 21 48 48 H 1.09004 * 109.74607 * 191.65203 * 24 23 21 49 49 H 1.07997 * 126.09722 * 359.86436 * 26 25 24 50 50 H 1.07998 * 125.72660 * 180.02562 * 28 27 26 51 51 H 1.09003 * 109.59745 * 77.58551 * 30 29 28 52 52 H 1.08996 * 109.59988 * 317.11188 * 30 29 28 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 1.3162 0.0000 0.0000 3 14 2.2502 1.6178 0.0000 4 1 1.2909 2.7431 -0.1367 5 1 2.9984 1.7574 1.2751 6 1 3.2036 1.6390 -1.1383 7 6 2.0103 -1.2021 -0.0005 8 1 1.4807 -2.1314 -0.1503 9 7 3.3665 -1.2098 0.1887 10 6 4.1291 -0.2273 0.9804 11 6 5.4208 -0.9726 1.3996 12 6 5.7142 -1.8226 0.1352 13 6 4.3025 -2.2027 -0.3586 14 1 4.0381 -3.1979 -0.0011 15 6 4.2623 -2.1682 -1.8877 16 6 2.9001 -2.6678 -2.3734 17 6 2.8989 -2.7405 -3.9017 18 7 1.5949 -3.2194 -4.3668 19 6 1.3612 -3.3632 -5.6863 20 8 2.2307 -3.0965 -6.4887 21 6 0.0195 -3.8553 -6.1647 22 1 -0.7583 -3.1671 -5.8339 23 6 0.0194 -3.9279 -7.6942 24 6 -1.4103 -4.1853 -8.1899 25 6 -1.9803 -5.3330 -7.3966 26 6 -3.0583 -6.0805 -7.6631 27 7 -3.1828 -6.9877 -6.6790 28 6 -2.2160 -6.8229 -5.8137 29 7 -1.4453 -5.8006 -6.2230 30 6 -0.2517 -5.2459 -5.5806 31 1 -0.4849 -0.8367 -0.0745 32 1 4.3740 0.6427 0.3712 33 1 3.5615 0.0728 1.8612 34 1 6.2311 -0.2705 1.5951 35 1 5.2408 -1.6093 2.2659 36 1 6.2423 -1.2313 -0.6129 37 1 6.2857 -2.7140 0.3938 38 1 4.4182 -1.1459 -2.2323 39 1 5.0479 -2.8098 -2.2864 40 1 2.7091 -3.6590 -1.9624 41 1 2.1217 -1.9807 -2.0417 42 1 3.0900 -1.7492 -4.3127 43 1 3.6773 -3.4276 -4.2334 44 1 0.8994 -3.4324 -3.7251 45 1 0.3820 -2.9848 -8.1031 46 1 0.6692 -4.7400 -8.0200 47 1 -2.0190 -3.2940 -8.0373 48 1 -1.3921 -4.4427 -9.2489 49 1 -3.7118 -5.9733 -8.5163 50 1 -2.0629 -7.4095 -4.9199 51 1 0.6024 -5.8952 -5.7731 52 1 -0.4184 -5.1659 -4.5064 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 ZINC001480823746.mol2 52 1SCF WAS SPECIFIED, SO GEOMETRY OPTIMIZATION WAS NOT USED SCF FIELD WAS ACHIEVED Wall clock time and date at job start Wed Apr 1 2020 03:56:06 Heat of formation + Delta-G solvation = 31.803616 kcal Electronic energy + Delta-G solvation = -30649.563015 eV Core-core repulsion = 26649.814005 eV Total energy + Delta-G solvation = -3999.749010 eV No. of doubly occupied orbitals = 66 Molecular weight (most abundant/longest-lived isotopes) = 346.211 amu Computer time = 1.04 seconds Orbital eigenvalues (eV) -42.57433 -40.04643 -38.24369 -36.57782 -35.44457 -33.33925 -32.81081 -32.66362 -31.00082 -29.85687 -28.71616 -27.91264 -25.39499 -24.69234 -23.81763 -22.68871 -21.65202 -21.57553 -20.73566 -20.28230 -19.33343 -19.13764 -17.65600 -17.45953 -17.06055 -16.09314 -15.90391 -15.82097 -15.41821 -15.04439 -14.70856 -14.43501 -14.28311 -14.14907 -13.88607 -13.62528 -13.49246 -13.35402 -13.16999 -12.76316 -12.56314 -12.29321 -12.06738 -11.99116 -11.75813 -11.65667 -11.50279 -11.29758 -11.17233 -11.12889 -10.70042 -10.44575 -10.31320 -10.20542 -10.11014 -9.97967 -9.80705 -9.76079 -9.48299 -9.12139 -9.05697 -8.59791 -8.54268 -7.08203 -6.31796 -3.44111 1.83513 2.30999 2.56932 2.97071 3.07995 3.37759 3.45594 3.64386 3.96892 4.19926 4.27755 4.43109 4.52617 4.55932 4.76701 4.81728 4.87876 4.94678 5.02324 5.12624 5.14312 5.21327 5.26001 5.34653 5.43609 5.47751 5.48875 5.52919 5.56633 5.73415 5.73973 5.83187 5.89815 5.95136 6.07558 6.08848 6.13694 6.20300 6.23220 6.32532 6.40216 6.52646 6.53094 6.60285 6.66762 6.75763 6.96476 6.97565 7.05207 7.42043 7.81813 7.86605 8.07497 8.27399 8.93790 9.47506 10.23419 11.07434 Molecular weight = 346.21amu Principal moments of inertia in cm(-1) A = 0.014519 B = 0.002339 C = 0.002243 Principal moments of inertia in units of 10**(-40)*gram-cm**2 A = 1928.053917 B =11967.265648 C =12480.719252 Net atomic charges, atomic populations, and dipole contributions calculated with CM2 Atom NO. Type Charge No. of electrons 1 N -0.925 5.925 2 C -0.013 4.013 3 Si 1.066 2.934 4 H -0.301 1.301 5 H -0.285 1.285 6 H -0.292 1.292 7 C -0.314 4.314 8 H 0.069 0.931 9 N -0.605 5.605 10 C 0.111 3.889 11 C -0.134 4.134 12 C -0.128 4.128 13 C 0.158 3.842 14 H 0.036 0.964 15 C -0.113 4.113 16 C -0.137 4.137 17 C 0.120 3.880 18 N -0.721 5.721 19 C 0.519 3.481 20 O -0.536 6.536 21 C -0.122 4.122 22 H 0.110 0.890 23 C -0.104 4.104 24 C -0.047 4.047 25 C -0.024 4.024 26 C -0.026 4.026 27 N -0.497 5.497 28 C 0.185 3.815 29 N -0.455 5.455 30 C 0.114 3.886 31 H 0.261 0.739 32 H 0.022 0.978 33 H 0.057 0.943 34 H 0.062 0.938 35 H 0.065 0.935 36 H 0.064 0.936 37 H 0.061 0.939 38 H 0.059 0.941 39 H 0.045 0.955 40 H 0.053 0.947 41 H 0.111 0.889 42 H 0.065 0.935 43 H 0.059 0.941 44 H 0.402 0.598 45 H 0.089 0.911 46 H 0.073 0.927 47 H 0.085 0.915 48 H 0.091 0.909 49 H 0.169 0.831 50 H 0.205 0.795 51 H 0.091 0.909 52 H 0.099 0.901 For the charges calculated by CM2: Dipole moment (debyes) X Y Z Total from point charges 2.994 -9.391 -10.819 14.636 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 -0.565 5.565 2 C -0.215 4.215 3 Si 0.899 3.101 4 H -0.229 1.229 5 H -0.213 1.213 6 H -0.219 1.219 7 C -0.442 4.442 8 H 0.087 0.913 9 N -0.331 5.331 10 C -0.014 4.014 11 C -0.172 4.172 12 C -0.166 4.166 13 C 0.051 3.949 14 H 0.054 0.946 15 C -0.153 4.153 16 C -0.175 4.175 17 C -0.003 4.003 18 N -0.371 5.371 19 C 0.303 3.697 20 O -0.413 6.413 21 C -0.144 4.144 22 H 0.128 0.872 23 C -0.142 4.142 24 C -0.085 4.085 25 C -0.138 4.138 26 C -0.173 4.173 27 N -0.215 5.215 28 C -0.097 4.097 29 N -0.138 5.138 30 C -0.009 4.009 31 H 0.071 0.929 32 H 0.040 0.960 33 H 0.075 0.925 34 H 0.080 0.920 35 H 0.084 0.916 36 H 0.083 0.917 37 H 0.080 0.920 38 H 0.078 0.922 39 H 0.064 0.936 40 H 0.072 0.928 41 H 0.129 0.871 42 H 0.083 0.917 43 H 0.077 0.923 44 H 0.237 0.763 45 H 0.108 0.892 46 H 0.092 0.908 47 H 0.103 0.897 48 H 0.110 0.890 49 H 0.186 0.814 50 H 0.222 0.778 51 H 0.109 0.891 52 H 0.118 0.882 Dipole moment (debyes) X Y Z Total from point charges 2.842 -8.118 -11.181 14.106 hybrid contribution 0.524 -1.212 0.366 1.370 sum 3.365 -9.330 -10.814 14.674 Atomic orbital electron populations 1.70953 1.05822 1.29563 1.50207 1.26129 0.96535 1.01277 0.97521 0.83813 0.73763 0.75856 0.76702 1.22868 1.21261 1.21931 1.19902 0.80335 0.94331 1.49623 0.91308 1.44819 1.02948 1.29601 1.55774 1.22120 0.91827 0.92697 0.94775 1.22740 0.98037 0.98917 0.97506 1.22604 0.97029 0.99372 0.97605 1.21033 0.88890 0.93737 0.91217 0.94629 1.21839 0.95172 1.00459 0.97831 1.22073 1.01629 1.02590 0.91184 1.21554 0.83247 0.99288 0.96251 1.46150 1.17183 1.66984 1.06796 1.20132 0.88638 0.78240 0.82673 1.90714 1.46059 1.50450 1.54073 1.21651 0.97271 0.96717 0.98726 0.87190 1.21490 0.96442 1.04479 0.91796 1.20278 0.95184 0.94352 0.98688 1.21224 0.99152 1.02508 0.90928 1.21830 0.98671 0.96142 1.00627 1.70503 1.22448 1.24619 1.03907 1.24838 0.90291 0.92685 1.01842 1.45363 1.22698 1.26562 1.19216 1.21878 0.86599 0.94259 0.98140 0.92918 0.96040 0.92506 0.91958 0.91616 0.91696 0.91994 0.92206 0.93598 0.92834 0.87058 0.91675 0.92285 0.76341 0.89229 0.90800 0.89694 0.89018 0.81399 0.77815 0.89093 0.88240 Number of geometries 1 Number of calculations of the screened coulomb radii 1 The total number of SCF iterations 15. 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 -0.93 -27.03 13.70 55.49 0.76 -26.27 16 2 C -0.01 -0.36 5.49 -17.43 -0.10 -0.46 16 3 Si 1.07 25.57 24.78 -169.99 -4.21 21.36 16 4 H -0.30 -7.49 7.11 56.52 0.40 -7.09 16 5 H -0.29 -6.35 5.61 56.52 0.32 -6.03 16 6 H -0.29 -6.81 7.09 56.52 0.40 -6.41 16 7 C -0.31 -7.96 7.68 -15.06 -0.12 -8.08 16 8 H 0.07 1.84 7.49 -52.49 -0.39 1.44 16 9 N -0.60 -13.36 2.85 -162.58 -0.46 -13.82 16 10 C 0.11 2.26 4.52 -2.52 -0.01 2.25 16 11 C -0.13 -2.14 7.08 -24.58 -0.17 -2.31 16 12 C -0.13 -1.94 6.47 -24.90 -0.16 -2.10 16 13 C 0.16 2.86 3.24 -66.96 -0.22 2.64 16 14 H 0.04 0.66 8.14 -51.93 -0.42 0.24 16 15 C -0.11 -1.86 4.72 -26.73 -0.13 -1.99 16 16 C -0.14 -2.21 4.68 -26.73 -0.13 -2.34 16 17 C 0.12 1.72 5.67 -4.04 -0.02 1.70 16 18 N -0.72 -8.98 5.46 -60.29 -0.33 -9.31 16 19 C 0.52 6.52 7.14 -10.99 -0.08 6.44 16 20 O -0.54 -8.63 15.81 5.55 0.09 -8.54 16 21 C -0.12 -1.15 2.52 -91.58 -0.23 -1.38 16 22 H 0.11 1.01 8.11 -51.93 -0.42 0.59 16 23 C -0.10 -0.95 4.69 -26.42 -0.12 -1.08 16 24 C -0.05 -0.37 6.31 -27.62 -0.17 -0.55 16 25 C -0.02 -0.24 6.57 -81.72 -0.54 -0.78 16 26 C -0.03 -0.29 11.84 -17.95 -0.21 -0.50 16 27 N -0.50 -6.33 11.27 -14.87 -0.17 -6.50 16 28 C 0.19 1.93 12.66 -90.71 -1.15 0.78 16 29 N -0.45 -4.47 3.13 -114.11 -0.36 -4.82 16 30 C 0.11 0.94 6.12 -3.93 -0.02 0.91 16 31 H 0.26 7.48 8.73 -40.82 -0.36 7.12 16 32 H 0.02 0.46 5.42 -51.93 -0.28 0.18 16 33 H 0.06 1.24 6.79 -51.93 -0.35 0.89 16 34 H 0.06 0.85 8.14 -51.93 -0.42 0.43 16 35 H 0.07 1.02 8.14 -51.93 -0.42 0.60 16 36 H 0.06 0.93 7.86 -51.93 -0.41 0.53 16 37 H 0.06 0.80 8.14 -51.93 -0.42 0.38 16 38 H 0.06 1.08 8.14 -51.93 -0.42 0.65 16 39 H 0.05 0.64 8.14 -51.93 -0.42 0.22 16 40 H 0.05 0.82 8.14 -51.93 -0.42 0.40 16 41 H 0.11 2.24 5.29 -51.93 -0.27 1.96 16 42 H 0.06 1.04 8.14 -51.93 -0.42 0.62 16 43 H 0.06 0.82 8.14 -51.93 -0.42 0.40 16 44 H 0.40 4.38 8.09 -40.82 -0.33 4.05 16 45 H 0.09 0.87 7.77 -51.92 -0.40 0.47 16 46 H 0.07 0.72 8.12 -51.93 -0.42 0.30 16 47 H 0.08 0.61 8.14 -51.93 -0.42 0.19 16 48 H 0.09 0.59 8.14 -51.93 -0.42 0.17 16 49 H 0.17 1.50 8.06 -52.49 -0.42 1.07 16 50 H 0.21 1.42 8.06 -52.49 -0.42 1.00 16 51 H 0.09 0.72 8.12 -51.93 -0.42 0.29 16 52 H 0.10 0.66 7.84 -51.93 -0.41 0.25 16 LS Contribution 399.51 15.07 6.02 6.02 Total: -1.00 -32.71 399.51 -11.09 -43.80 By element: Atomic # 1 Polarization: 13.77 SS G_CDS: -8.85 Total: 4.92 kcal Atomic # 6 Polarization: -3.26 SS G_CDS: -3.58 Total: -6.83 kcal Atomic # 7 Polarization: -60.17 SS G_CDS: -0.56 Total: -60.73 kcal Atomic # 8 Polarization: -8.63 SS G_CDS: 0.09 Total: -8.54 kcal Atomic # 14 Polarization: 25.57 SS G_CDS: -4.21 Total: 21.36 kcal Total LS contribution 6.02 Total: 6.02 kcal Total: -32.71 -11.09 -43.80 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. ZINC001480823746.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 75.604 kcal (2) G-P(sol) polarization free energy of solvation -32.713 kcal (3) G-ENP(sol) elect.-nuc.-pol. free energy of system 42.891 kcal (4) G-CDS(sol) cavity-dispersion-solvent structure free energy -11.087 kcal (5) G-P-CDS(sol) = G-P(sol) + G-CDS(sol) = (2) + (4) -43.800 kcal (6) G-S(sol) free energy of system = (1) + (5) 31.804 kcal 1SCF WAS SPECIFIED, SO GEOMETRY OPTIMIZATION WAS NOT USED Total computer time = 1.04 seconds