Wall clock time and date at job start Sat Apr 11 2020 06:11:33 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 C 1.52992 * 1 3 3 O 1.42903 * 109.46865 * 2 1 4 4 C 1.42902 * 113.99790 * 184.98692 * 3 2 1 5 5 C 1.53001 * 109.47186 * 184.98321 * 4 3 2 6 6 C 1.52995 * 109.47290 * 175.23791 * 5 4 3 7 7 C 1.50696 * 112.85221 * 301.58577 * 6 5 4 8 8 O 1.21279 * 120.00248 * 115.36183 * 7 6 5 9 9 N 1.34780 * 119.99441 * 295.35795 * 7 6 5 10 10 C 1.47161 * 120.94723 * 355.03163 * 9 7 6 11 11 C 1.53296 * 108.37773 * 230.51575 * 10 9 7 12 12 O 1.42966 * 109.26064 * 307.77236 * 11 10 9 13 13 C 1.42958 * 114.16749 * 62.55657 * 12 11 10 14 14 H 1.09002 * 109.51050 * 57.38979 * 13 12 11 15 15 C 1.53001 * 109.51148 * 177.49300 * 13 12 11 16 16 N 1.46497 * 109.47019 * 299.99825 * 15 13 12 17 17 C 1.36936 * 120.00029 * 179.97438 * 16 15 13 18 18 H 1.08008 * 120.00021 * 0.02562 * 17 16 15 19 19 C 1.38809 * 120.00261 * 180.02562 * 17 16 15 20 20 N 1.31616 * 119.99979 * 0.02562 * 19 17 16 21 21 Si 1.86809 * 120.00004 * 180.02562 * 19 17 16 22 22 H 1.48500 * 109.47144 * 60.00264 * 21 19 17 23 23 H 1.48497 * 109.46835 * 180.02562 * 21 19 17 24 24 H 1.48495 * 109.46826 * 300.00155 * 21 19 17 25 25 C 1.47155 * 120.97621 * 175.09302 * 9 7 6 26 26 C 1.53785 * 113.68697 * 72.85323 * 6 5 4 27 27 C 1.53785 * 87.08307 * 89.12808 * 26 6 5 28 28 C 1.53782 * 113.61210 * 170.38430 * 6 5 4 29 29 H 1.09000 * 109.47217 * 299.99787 * 1 2 3 30 30 H 1.09000 * 109.47845 * 60.00057 * 1 2 3 31 31 H 1.09007 * 109.47370 * 179.97438 * 1 2 3 32 32 H 1.09005 * 109.46856 * 240.00549 * 2 1 3 33 33 H 1.08993 * 109.47313 * 120.00356 * 2 1 3 34 34 H 1.08998 * 109.47592 * 64.97970 * 4 3 2 35 35 H 1.09005 * 109.46887 * 304.97848 * 4 3 2 36 36 H 1.09006 * 109.47391 * 55.23769 * 5 4 3 37 37 H 1.08999 * 109.46577 * 295.24070 * 5 4 3 38 38 H 1.09007 * 109.64560 * 110.81568 * 10 9 7 39 39 H 1.09000 * 109.72925 * 350.26282 * 10 9 7 40 40 H 1.09001 * 109.51560 * 187.82572 * 11 10 9 41 41 H 1.08999 * 109.51392 * 67.71997 * 11 10 9 42 42 H 1.09001 * 109.46897 * 60.00201 * 15 13 12 43 43 H 1.09003 * 109.46883 * 179.97438 * 15 13 12 44 44 H 0.97000 * 120.00070 * 0.02562 * 16 15 13 45 45 H 0.97004 * 119.99645 * 179.97438 * 20 19 17 46 46 H 1.08995 * 109.68661 * 9.71462 * 25 9 7 47 47 H 1.08996 * 109.68250 * 249.15737 * 25 9 7 48 48 H 1.08998 * 113.61141 * 203.67496 * 26 6 5 49 49 H 1.08993 * 113.61790 * 334.57531 * 26 6 5 50 50 H 1.08997 * 113.60758 * 270.88420 * 27 26 6 51 51 H 1.08997 * 113.61339 * 139.98200 * 27 26 6 52 52 H 1.08992 * 113.61632 * 25.35274 * 28 6 5 53 53 H 1.09008 * 113.61274 * 156.17197 * 28 6 5 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 6 1.5299 0.0000 0.0000 3 8 2.0062 1.3473 0.0000 4 6 3.4261 1.4618 -0.1135 5 6 3.8317 2.9309 0.0216 6 6 5.3577 3.0409 0.0192 7 6 6.0033 2.2497 1.1274 8 8 6.7224 1.3099 0.8621 9 7 5.7815 2.5867 2.4134 10 6 5.0021 3.7865 2.7577 11 6 5.8042 4.6092 3.7724 12 8 6.1906 3.7678 4.8617 13 6 7.0515 2.6884 4.4907 14 1 7.9469 3.0849 4.0120 15 6 7.4470 1.8978 5.7395 16 7 8.1476 2.7811 6.6751 17 6 8.5992 2.2913 7.8714 18 1 8.4393 1.2537 8.1251 19 6 9.2625 3.1283 8.7581 20 7 9.4569 4.3928 8.4493 21 14 9.8792 2.4598 10.3899 22 1 10.8473 1.3616 10.1408 23 1 10.5477 3.5469 11.1491 24 1 8.7324 1.9398 11.1769 25 6 6.3128 1.7666 3.5137 26 6 5.9924 2.7994 -1.3606 27 6 5.8302 4.3079 -1.6120 28 6 5.8708 4.4869 -0.0852 29 1 -0.3634 0.5138 0.8900 30 1 -0.3635 0.5138 -0.8899 31 1 -0.3634 -1.0277 -0.0005 32 1 1.8932 -0.5138 -0.8901 33 1 1.8933 -0.5138 0.8899 34 1 3.7446 1.0849 -1.0854 35 1 3.9018 0.8795 0.6757 36 1 3.4401 3.3315 0.9567 37 1 3.4251 3.4985 -0.8154 38 1 4.0489 3.4909 3.1963 39 1 4.8256 4.3805 1.8610 40 1 5.1887 5.4279 4.1454 41 1 6.6947 5.0133 3.2909 42 1 6.5513 1.5001 6.2166 43 1 8.1030 1.0748 5.4558 44 1 8.2908 3.7130 6.4474 45 1 9.9201 4.9778 9.0691 46 1 7.0038 1.0230 3.1168 47 1 5.4921 1.2677 4.0290 48 1 7.0315 2.4741 -1.3123 49 1 5.3838 2.1792 -2.0186 50 1 4.8722 4.5757 -2.0576 51 1 6.6785 4.7583 -2.1272 52 1 5.1642 5.2288 0.2864 53 1 6.8763 4.6232 0.3131 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 ZINC001484678434.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 06:11:33 Heat of formation + Delta-G solvation = -91.091195 kcal Electronic energy + Delta-G solvation = -31328.386112 eV Core-core repulsion = 27201.473843 eV Total energy + Delta-G solvation = -4126.912269 eV No. of doubly occupied orbitals = 66 Molecular weight (most abundant/longest-lived isotopes) = 340.220 amu Computer time = 0.84 seconds Orbital eigenvalues (eV) -41.35883 -39.18237 -38.21356 -37.57901 -35.06671 -34.37427 -32.69240 -32.19652 -30.61159 -30.13579 -28.25055 -26.83167 -25.91690 -25.00596 -23.53739 -23.10183 -23.08839 -22.32258 -20.93127 -20.10321 -18.65274 -17.32923 -17.04185 -16.97738 -16.72431 -16.44661 -16.07000 -15.56248 -15.36348 -15.12060 -14.82312 -14.58163 -14.42866 -14.28361 -14.00607 -13.48144 -13.18071 -13.06160 -12.95937 -12.76503 -12.69142 -12.54634 -12.40523 -12.31239 -12.04414 -11.78722 -11.62151 -11.52331 -11.36456 -11.32136 -10.97216 -10.89410 -10.83000 -10.76530 -10.65298 -10.36844 -10.07296 -9.90211 -9.86721 -9.71858 -9.57517 -8.84184 -8.51870 -6.87082 -5.70762 -2.99382 2.45865 2.76534 3.21178 3.47864 3.51590 3.52994 3.95239 4.00027 4.13788 4.27495 4.43400 4.49877 4.60299 4.68466 4.72230 4.75841 4.82386 4.90680 4.96270 5.02176 5.06298 5.10558 5.15961 5.17954 5.29737 5.32975 5.36998 5.42232 5.44290 5.49510 5.54760 5.55896 5.61648 5.63876 5.67126 5.70567 5.74161 5.76837 5.81406 5.89629 5.96943 6.04999 6.28984 6.34229 6.57441 6.71146 6.85835 7.25538 7.47833 7.73149 8.02649 8.47452 9.59057 10.16411 10.52615 11.52000 Molecular weight = 340.22amu Principal moments of inertia in cm(-1) A = 0.014778 B = 0.002469 C = 0.002272 Principal moments of inertia in units of 10**(-40)*gram-cm**2 A = 1894.197816 B =11336.747613 C =12319.850703 Net atomic charges, atomic populations, and dipole contributions calculated with CM2 Atom NO. Type Charge No. of electrons 1 C -0.151 4.151 2 C 0.057 3.943 3 O -0.390 6.390 4 C 0.064 3.936 5 C -0.093 4.093 6 C -0.105 4.105 7 C 0.530 3.470 8 O -0.539 6.539 9 N -0.608 5.608 10 C 0.065 3.935 11 C 0.046 3.954 12 O -0.356 6.356 13 C 0.075 3.925 14 H 0.062 0.938 15 C 0.164 3.836 16 N -0.725 5.725 17 C -0.239 4.239 18 H 0.070 0.930 19 C -0.014 4.014 20 N -0.932 5.932 21 Si 0.908 3.092 22 H -0.286 1.286 23 H -0.291 1.291 24 H -0.286 1.286 25 C 0.084 3.916 26 C -0.112 4.112 27 C -0.140 4.140 28 C -0.125 4.125 29 H 0.063 0.937 30 H 0.062 0.938 31 H 0.070 0.930 32 H 0.047 0.953 33 H 0.049 0.951 34 H 0.052 0.948 35 H 0.049 0.951 36 H 0.083 0.917 37 H 0.085 0.915 38 H 0.077 0.923 39 H 0.098 0.902 40 H 0.104 0.896 41 H 0.053 0.947 42 H 0.028 0.972 43 H 0.035 0.965 44 H 0.388 0.612 45 H 0.255 0.745 46 H 0.100 0.900 47 H 0.077 0.923 48 H 0.093 0.907 49 H 0.073 0.927 50 H 0.085 0.915 51 H 0.074 0.926 52 H 0.080 0.920 53 H 0.089 0.911 For the charges calculated by CM2: Dipole moment (debyes) X Y Z Total from point charges -15.996 -1.450 -23.949 28.836 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 -0.208 4.208 2 C -0.019 4.019 3 O -0.309 6.309 4 C -0.013 4.013 5 C -0.130 4.130 6 C -0.108 4.108 7 C 0.318 3.682 8 O -0.415 6.415 9 N -0.342 5.342 10 C -0.058 4.058 11 C -0.032 4.032 12 O -0.274 6.274 13 C 0.016 3.984 14 H 0.080 0.920 15 C 0.035 3.965 16 N -0.370 5.370 17 C -0.371 4.371 18 H 0.088 0.912 19 C -0.210 4.210 20 N -0.581 5.581 21 Si 0.739 3.261 22 H -0.213 1.213 23 H -0.217 1.217 24 H -0.213 1.213 25 C -0.039 4.039 26 C -0.150 4.150 27 C -0.177 4.177 28 C -0.163 4.163 29 H 0.083 0.917 30 H 0.081 0.919 31 H 0.089 0.911 32 H 0.066 0.934 33 H 0.067 0.933 34 H 0.070 0.930 35 H 0.067 0.933 36 H 0.101 0.899 37 H 0.104 0.896 38 H 0.095 0.905 39 H 0.116 0.884 40 H 0.122 0.878 41 H 0.071 0.929 42 H 0.046 0.954 43 H 0.052 0.948 44 H 0.222 0.778 45 H 0.065 0.935 46 H 0.119 0.881 47 H 0.095 0.905 48 H 0.112 0.888 49 H 0.091 0.909 50 H 0.103 0.897 51 H 0.092 0.908 52 H 0.099 0.901 53 H 0.108 0.892 Dipole moment (debyes) X Y Z Total from point charges -15.751 -1.880 -23.737 28.550 hybrid contribution 0.600 -0.292 0.691 0.961 sum -15.151 -2.172 -23.046 27.666 Atomic orbital electron populations 1.21745 0.93641 1.02299 1.03119 1.22460 0.95581 0.83670 1.00230 1.87835 1.21413 1.26672 1.95012 1.22428 0.81304 0.97012 1.00527 1.21327 0.91081 0.96185 1.04422 1.22084 0.95706 0.97670 0.95366 1.20380 0.80674 0.84204 0.82910 1.90689 1.37994 1.29903 1.82955 1.48120 1.53606 1.26908 1.05559 1.22748 0.95494 0.87052 1.00521 1.22918 0.98479 0.93151 0.88685 1.88170 1.67059 1.40841 1.31303 1.22775 0.91703 0.87701 0.96230 0.91984 1.20621 0.95383 0.92529 0.87935 1.42199 1.67353 1.09959 1.17478 1.19182 1.29275 0.94788 0.93813 0.91230 1.24741 1.01644 0.95738 0.98858 1.69667 1.47357 1.04193 1.36857 0.86252 0.78536 0.77497 0.83802 1.21290 1.21713 1.21275 1.22351 0.99667 0.94474 0.87400 1.22860 1.02065 0.96653 0.93426 1.22849 1.02584 0.96466 0.95807 1.23045 1.02155 0.93695 0.97372 0.91741 0.91921 0.91079 0.93445 0.93290 0.92952 0.93309 0.89863 0.89644 0.90459 0.88407 0.87795 0.92893 0.95428 0.94758 0.77825 0.93526 0.88132 0.90499 0.88836 0.90853 0.89683 0.90766 0.90133 0.89222 Number of geometries 1 Number of calculations of the screened coulomb radii 1 The total number of SCF iterations 14. 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 -0.15 -1.01 10.28 37.15 0.38 -0.62 16 2 C 0.06 0.48 6.66 37.15 0.25 0.72 16 3 O -0.39 -4.01 10.34 -35.23 -0.36 -4.37 16 4 C 0.06 0.62 5.66 37.16 0.21 0.83 16 5 C -0.09 -0.76 4.63 -26.73 -0.12 -0.89 16 6 C -0.11 -0.96 0.29 -154.85 -0.04 -1.01 16 7 C 0.53 6.85 5.52 -10.99 -0.06 6.79 16 8 O -0.54 -8.82 15.60 5.56 0.09 -8.73 16 9 N -0.61 -7.77 3.02 -172.27 -0.52 -8.29 16 10 C 0.06 0.67 5.08 -3.53 -0.02 0.66 16 11 C 0.05 0.57 6.98 37.31 0.26 0.83 16 12 O -0.36 -6.29 10.13 -35.23 -0.36 -6.65 16 13 C 0.07 1.30 2.87 -26.58 -0.08 1.23 16 14 H 0.06 1.14 8.14 -51.93 -0.42 0.71 16 15 C 0.16 3.42 5.96 -4.04 -0.02 3.40 16 16 N -0.73 -19.19 5.49 -59.91 -0.33 -19.52 16 17 C -0.24 -6.90 9.99 -15.06 -0.15 -7.05 16 18 H 0.07 1.93 7.83 -52.48 -0.41 1.52 16 19 C -0.01 -0.41 5.50 -17.43 -0.10 -0.50 16 20 N -0.93 -28.88 13.06 55.49 0.72 -28.16 16 21 Si 0.91 22.85 29.55 -169.99 -5.02 17.82 16 22 H -0.29 -7.06 7.11 56.52 0.40 -6.66 16 23 H -0.29 -7.35 7.11 56.52 0.40 -6.95 16 24 H -0.29 -7.07 7.11 56.52 0.40 -6.67 16 25 C 0.08 1.23 5.94 -3.53 -0.02 1.21 16 26 C -0.11 -0.96 6.78 -25.91 -0.18 -1.14 16 27 C -0.14 -0.91 7.73 -25.92 -0.20 -1.11 16 28 C -0.13 -0.93 5.77 -25.92 -0.15 -1.08 16 29 H 0.06 0.45 8.14 -51.93 -0.42 0.03 16 30 H 0.06 0.40 8.14 -51.93 -0.42 -0.02 16 31 H 0.07 0.36 8.14 -51.92 -0.42 -0.06 16 32 H 0.05 0.35 8.14 -51.93 -0.42 -0.07 16 33 H 0.05 0.41 8.14 -51.93 -0.42 -0.01 16 34 H 0.05 0.47 7.36 -51.93 -0.38 0.09 16 35 H 0.05 0.56 7.19 -51.93 -0.37 0.18 16 36 H 0.08 0.68 6.06 -51.93 -0.31 0.37 16 37 H 0.09 0.59 7.30 -51.93 -0.38 0.21 16 38 H 0.08 0.78 8.14 -51.92 -0.42 0.36 16 39 H 0.10 0.77 3.48 -51.93 -0.18 0.59 16 40 H 0.10 1.09 8.14 -51.93 -0.42 0.67 16 41 H 0.05 0.66 8.14 -51.93 -0.42 0.23 16 42 H 0.03 0.59 8.14 -51.93 -0.42 0.16 16 43 H 0.03 0.70 8.14 -51.93 -0.42 0.28 16 44 H 0.39 10.89 7.54 -40.82 -0.31 10.59 16 45 H 0.25 7.62 8.31 -40.82 -0.34 7.28 16 46 H 0.10 1.55 7.06 -51.93 -0.37 1.18 16 47 H 0.08 1.09 8.14 -51.93 -0.42 0.67 16 48 H 0.09 0.96 7.70 -51.93 -0.40 0.56 16 49 H 0.07 0.58 7.30 -51.93 -0.38 0.20 16 50 H 0.08 0.45 7.60 -51.93 -0.39 0.06 16 51 H 0.07 0.45 8.14 -51.93 -0.42 0.03 16 52 H 0.08 0.47 7.03 -51.93 -0.36 0.11 16 53 H 0.09 0.77 8.09 -51.92 -0.42 0.35 16 LS Contribution 409.87 15.07 6.18 6.18 Total: -1.00 -34.53 409.87 -8.95 -43.48 By element: Atomic # 1 Polarization: 15.28 SS G_CDS: -9.31 Total: 5.98 kcal Atomic # 6 Polarization: 2.31 SS G_CDS: -0.04 Total: 2.27 kcal Atomic # 7 Polarization: -55.85 SS G_CDS: -0.12 Total: -55.97 kcal Atomic # 8 Polarization: -19.12 SS G_CDS: -0.63 Total: -19.75 kcal Atomic # 14 Polarization: 22.85 SS G_CDS: -5.02 Total: 17.82 kcal Total LS contribution 6.18 Total: 6.18 kcal Total: -34.53 -8.95 -43.48 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. ZINC001484678434.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 -47.611 kcal (2) G-P(sol) polarization free energy of solvation -34.528 kcal (3) G-ENP(sol) elect.-nuc.-pol. free energy of system -82.139 kcal (4) G-CDS(sol) cavity-dispersion-solvent structure free energy -8.952 kcal (5) G-P-CDS(sol) = G-P(sol) + G-CDS(sol) = (2) + (4) -43.480 kcal (6) G-S(sol) free energy of system = (1) + (5) -91.091 kcal 1SCF WAS SPECIFIED, SO GEOMETRY OPTIMIZATION WAS NOT USED Total computer time = 0.84 seconds