Wall clock time and date at job start Mon Mar 8 2021 08:19:21 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= 0 * 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 1.53000 * 1 3 3 O 1.45197 * 109.46849 * 2 1 4 4 C 1.34227 * 117.00106 * 180.02562 * 3 2 1 5 5 O 1.20824 * 120.00207 * 359.97438 * 4 3 2 6 6 C 1.50697 * 120.00113 * 180.02562 * 4 3 2 7 7 H 1.09000 * 109.47741 * 59.99425 * 6 4 3 8 8 C 1.53001 * 109.47449 * 179.97438 * 6 4 3 9 9 C 1.53000 * 109.47629 * 179.97438 * 8 6 4 10 10 C 1.52998 * 109.47146 * 300.00290 * 9 8 6 11 11 F 1.39903 * 109.47066 * 300.00035 * 10 9 8 12 12 C 1.52997 * 109.47389 * 179.97438 * 10 9 8 13 13 S 1.81397 * 109.47484 * 184.99865 * 12 10 9 14 14 O 1.42093 * 110.54435 * 68.37248 * 13 12 10 15 15 O 1.42103 * 110.54023 * 291.62714 * 13 12 10 16 16 O 1.52193 * 104.45261 * 180.02562 * 13 12 10 17 17 C 1.35922 * 114.00501 * 74.99416 * 16 13 12 18 18 C 1.38715 * 120.02645 * 90.00087 * 17 16 13 19 19 C 1.50704 * 119.99598 * 359.75212 * 18 17 16 20 20 O 1.42896 * 109.47122 * 75.00183 * 19 18 17 21 21 Si 1.86297 * 109.46822 * 194.99952 * 19 18 17 22 22 C 1.38185 * 120.00141 * 179.72964 * 18 17 16 23 23 C 1.38293 * 120.07018 * 359.97438 * 22 18 17 24 24 Cl 1.73597 * 119.96707 * 180.02562 * 23 22 18 25 25 C 1.38611 * 120.06026 * 359.97438 * 23 22 18 26 26 F 1.35096 * 120.00222 * 180.02562 * 25 23 22 27 27 C 1.38329 * 119.99288 * 0.03822 * 25 23 22 28 28 C 1.52999 * 109.47559 * 59.99636 * 10 9 8 29 29 C 1.53006 * 109.46946 * 299.99652 * 6 4 3 30 30 H 1.09008 * 109.47037 * 179.97438 * 1 2 3 31 31 H 1.09001 * 109.47151 * 299.99621 * 1 2 3 32 32 H 1.08993 * 109.47330 * 60.00139 * 1 2 3 33 33 H 1.08994 * 109.47170 * 240.00023 * 2 1 3 34 34 H 1.09001 * 109.47058 * 119.99684 * 2 1 3 35 35 H 1.09008 * 109.46956 * 59.99492 * 8 6 4 36 36 H 1.08999 * 109.47096 * 300.00375 * 8 6 4 37 37 H 1.08996 * 109.47354 * 179.97438 * 9 8 6 38 38 H 1.09002 * 109.46684 * 60.00021 * 9 8 6 39 39 H 1.09005 * 109.47030 * 64.99975 * 12 10 9 40 40 H 1.09000 * 109.47022 * 305.00269 * 12 10 9 41 41 H 1.09004 * 109.47155 * 314.99598 * 19 18 17 42 42 H 0.96709 * 113.99757 * 299.99129 * 20 19 18 43 43 H 1.48508 * 110.00113 * 298.68005 * 21 19 18 44 44 H 1.48504 * 110.00293 * 59.99823 * 21 19 18 45 45 H 1.08000 * 119.96213 * 179.97438 * 22 18 17 46 46 H 1.07999 * 120.02742 * 179.97438 * 27 25 23 47 47 H 1.09002 * 109.47045 * 59.99794 * 28 10 9 48 48 H 1.08996 * 109.47615 * 180.02562 * 28 10 9 49 49 H 1.08994 * 109.46998 * 300.00088 * 29 6 4 50 50 H 1.08998 * 109.46761 * 60.00138 * 29 6 4 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 1.5300 0.0000 0.0000 3 8 2.0139 1.3690 0.0000 4 6 3.3446 1.5449 -0.0005 5 8 4.0807 0.5868 -0.0005 6 6 3.9205 2.9375 0.0000 7 1 3.5850 3.4692 0.8904 8 6 5.4485 2.8576 -0.0001 9 6 6.0332 4.2714 -0.0002 10 6 5.5615 5.0183 -1.2494 11 9 5.9926 4.3353 -2.3917 12 6 6.1457 6.4324 -1.2492 13 16 5.4702 7.3660 -2.6501 14 8 4.0848 7.6180 -2.4598 15 8 5.9579 6.8442 -3.8786 16 8 6.1202 8.7378 -2.5411 17 6 7.4232 8.7645 -2.9272 18 6 7.7501 9.0279 -4.2493 19 6 6.6602 9.2790 -5.2593 20 8 6.1227 10.5886 -5.0644 21 14 7.3646 9.1465 -6.9789 22 6 9.0751 9.0605 -4.6401 23 6 10.0765 8.8312 -3.7143 24 17 11.7402 8.8734 -4.2080 25 6 9.7529 8.5688 -2.3922 26 9 10.7321 8.3455 -1.4887 27 6 8.4274 8.5354 -1.9983 28 6 4.0336 5.0984 -1.2493 29 6 3.4484 3.6851 -1.2487 30 1 -0.3633 -1.0277 -0.0005 31 1 -0.3633 0.5138 0.8900 32 1 -0.3633 0.5138 -0.8899 33 1 1.8933 -0.5138 -0.8899 34 1 1.8933 -0.5138 0.8900 35 1 5.7844 2.3257 -0.8904 36 1 5.7845 2.3250 0.8896 37 1 7.1217 4.2144 0.0002 38 1 5.6973 4.8035 0.8898 39 1 7.2307 6.3772 -1.3387 40 1 5.8830 6.9339 -0.3178 41 1 5.8698 8.5392 -5.1325 42 1 5.7378 10.7295 -4.1884 43 1 8.4215 10.1711 -7.1752 44 1 7.9269 7.7891 -7.1943 45 1 9.3290 9.2652 -5.6697 46 1 8.1746 8.3306 -0.9684 47 1 3.6977 5.6305 -0.3593 48 1 3.6975 5.6301 -2.1394 49 1 3.7840 3.1535 -2.1390 50 1 2.3599 3.7421 -1.2481 There are 78 doubly filled levels RHF calculation, no. of doubly occupied orbitals= 78 No. of singly occupied orbitals= 1 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) O: (AM1): M.J.S. DEWAR ET AL, J. AM. CHEM. SOC. 107 3902-3909 (1985) F: (AM1): M.J.S. DEWAR AND E. G. ZOEBISCH, THEOCHEM, 180, 1 (1988). 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) Cl: (AM1): M.J.S. DEWAR AND E. G. ZOEBISCH, THEOCHEM, 180, 1 (1988). 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=0 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 s_40_10548610_16464698.mol2 50 1SCF WAS SPECIFIED, SO GEOMETRY OPTIMIZATION WAS NOT USED SCF FIELD WAS ACHIEVED Wall clock time and date at job start Mon Mar 8 2021 08:19:21 Heat of formation + Delta-G solvation = -285.175163 kcal Electronic energy + Delta-G solvation = -43607.922846 eV Core-core repulsion = 37585.204559 eV Total energy + Delta-G solvation = -6022.718287 eV No. of doubly occupied orbitals = 78 and no. of open levels = 1 Molecular weight (most abundant/longest-lived isotopes) = 455.084 amu Computer time = 1.66 seconds Orbital eigenvalues (eV) -50.47319 -49.17893 -42.95353 -41.71178 -39.91175 -39.25407 -38.62519 -38.14844 -37.67935 -37.57579 -37.38904 -34.44000 -33.14434 -32.70257 -32.28435 -31.87369 -29.31725 -27.20972 -25.64454 -25.08468 -24.37947 -23.76094 -23.61111 -22.25892 -21.90301 -21.01131 -20.14685 -19.58563 -19.38519 -18.74819 -18.71471 -18.17948 -18.01863 -17.88777 -17.67273 -17.46381 -17.23996 -17.18209 -16.90848 -16.52777 -16.30687 -16.16130 -15.76787 -15.67373 -15.33716 -15.10812 -15.01389 -14.79188 -14.66394 -14.53190 -14.32795 -14.22137 -14.12375 -13.96732 -13.88516 -13.85950 -13.70848 -13.54219 -13.42837 -13.37703 -13.36802 -13.23455 -12.91330 -12.82270 -12.72616 -12.56569 -12.49052 -12.40190 -12.19023 -12.10981 -11.89713 -11.65319 -11.53069 -11.38941 -11.27554 -11.23207 -10.72672 -10.20745 -4.93782 -1.62284 -0.78232 -0.74382 0.40891 0.54967 1.16028 1.19358 1.46882 1.58015 1.64235 1.78015 2.01377 2.34372 2.41457 2.55388 2.80674 2.84378 2.92532 2.94318 3.11360 3.17289 3.35364 3.39023 3.47785 3.59991 3.61391 3.74394 3.76335 3.82635 3.88639 3.93340 3.97400 3.97932 4.01504 4.05986 4.08761 4.15139 4.21037 4.26918 4.33009 4.40569 4.49082 4.54010 4.61000 4.66642 4.75492 4.78326 4.81229 4.86830 4.92889 5.00046 5.07385 5.44890 6.33431 6.71988 Net atomic charges, atomic populations, and dipole contributions calculated with CM2 Atom NO. Type Charge No. of electrons 1 C -0.154 4.154 2 C 0.061 3.939 3 O -0.356 6.356 4 C 0.467 3.533 5 O -0.503 6.503 6 C -0.083 4.083 7 H 0.115 0.885 8 C -0.110 4.110 9 C -0.129 4.129 10 C 0.138 3.862 11 F -0.187 7.187 12 C -0.687 4.687 13 S 2.585 3.415 14 O -0.904 6.904 15 O -0.925 6.925 16 O -0.657 6.657 17 C 0.107 3.893 18 C -0.074 4.074 19 C -0.104 4.104 20 O -0.525 6.525 21 Si 0.756 3.244 22 C -0.067 4.067 23 C -0.051 4.051 24 Cl -0.018 7.018 25 C 0.137 3.863 26 F -0.107 7.107 27 C -0.153 4.153 28 C -0.171 4.171 29 C -0.111 4.111 30 H 0.081 0.919 31 H 0.067 0.933 32 H 0.068 0.932 33 H 0.071 0.929 34 H 0.071 0.929 35 H 0.084 0.916 36 H 0.086 0.914 37 H 0.089 0.911 38 H 0.092 0.908 39 H 0.150 0.850 40 H 0.163 0.837 41 H 0.093 0.907 42 H 0.369 0.631 43 H -0.244 1.244 44 H -0.235 1.235 45 H 0.161 0.839 46 H 0.169 0.831 47 H 0.105 0.895 48 H 0.093 0.907 49 H 0.081 0.919 50 H 0.095 0.905 For the charges calculated by CM2: Dipole moment (debyes) X Y Z Total from point charges -2.008 0.926 2.435 3.289 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 -0.211 4.211 2 C -0.013 4.013 3 O -0.273 6.273 4 C 0.309 3.691 5 O -0.390 6.390 6 C -0.102 4.102 7 H 0.133 0.867 8 C -0.147 4.147 9 C -0.167 4.167 10 C 0.118 3.882 11 F -0.167 7.167 12 C -0.812 4.812 13 S 2.680 3.320 14 O -0.902 6.902 15 O -0.924 6.924 16 O -0.615 6.615 17 C 0.065 3.935 18 C -0.077 4.077 19 C -0.212 4.212 20 O -0.331 6.331 21 Si 0.651 3.349 22 C -0.085 4.085 23 C -0.080 4.080 24 Cl 0.012 6.988 25 C 0.117 3.883 26 F -0.085 7.085 27 C -0.174 4.174 28 C -0.209 4.209 29 C -0.149 4.149 30 H 0.100 0.900 31 H 0.086 0.914 32 H 0.087 0.913 33 H 0.090 0.910 34 H 0.089 0.911 35 H 0.103 0.897 36 H 0.105 0.895 37 H 0.108 0.892 38 H 0.110 0.890 39 H 0.168 0.832 40 H 0.181 0.819 41 H 0.111 0.889 42 H 0.217 0.783 43 H -0.168 1.168 44 H -0.159 1.159 45 H 0.178 0.822 46 H 0.186 0.814 47 H 0.124 0.876 48 H 0.111 0.889 49 H 0.100 0.900 50 H 0.113 0.887 Dipole moment (debyes) X Y Z Total from point charges -1.206 0.839 0.836 1.690 hybrid contribution 0.676 -0.623 2.730 2.881 sum -0.530 0.216 3.567 3.612 Atomic orbital electron populations 1.21824 0.92260 1.03300 1.03692 1.23094 0.95642 0.79757 1.02781 1.86497 1.24249 1.32843 1.83747 1.23566 0.80790 0.92373 0.72364 1.90696 1.60457 1.43041 1.44821 1.21169 0.96623 0.90317 1.02076 0.86693 1.21486 0.91709 0.96263 1.05273 1.22105 1.02628 0.96022 0.95944 1.20474 0.94862 0.87199 0.85615 1.92989 1.91123 1.81007 1.51612 1.31581 1.15048 1.10403 1.24204 1.05995 0.75623 0.73708 0.76714 1.93706 1.28136 1.81725 1.86621 1.93699 1.80468 1.78679 1.39529 1.85759 1.30542 1.58461 1.86772 1.17420 0.78131 1.05682 0.92309 1.20545 0.95958 0.97723 0.93484 1.25717 0.96762 0.88719 1.09995 1.86788 1.78945 1.28840 1.38492 0.92398 0.82429 0.80817 0.79229 1.20843 0.89797 0.97617 1.00240 1.21143 0.89072 1.04847 0.92903 1.98457 1.12952 1.96373 1.91064 1.16809 0.85039 1.01030 0.85447 1.91644 1.60033 1.91465 1.65402 1.21196 0.90194 1.04415 1.01562 1.22695 0.91826 0.99794 1.06561 1.21489 1.02523 0.93814 0.97027 0.89988 0.91358 0.91301 0.91050 0.91100 0.89703 0.89535 0.89197 0.88968 0.83202 0.81925 0.88906 0.78283 1.16837 1.15881 0.82181 0.81395 0.87643 0.88867 0.90013 0.88659 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 C -0.15 0.28 10.29 37.16 0.38 0.66 16 2 C 0.06 0.01 6.19 37.16 0.23 0.24 16 3 O -0.36 -0.44 10.12 -39.25 -0.40 -0.84 16 4 C 0.47 0.78 7.25 36.00 0.26 1.04 16 5 O -0.50 -2.33 15.73 -18.75 -0.29 -2.63 16 6 C -0.08 0.10 2.63 -91.77 -0.24 -0.14 16 7 H 0.12 -0.40 8.14 -51.93 -0.42 -0.83 16 8 C -0.11 0.13 4.37 -26.73 -0.12 0.01 16 9 C -0.13 0.39 5.00 -26.73 -0.13 0.26 16 10 C 0.14 -0.21 0.89 -90.62 -0.08 -0.29 16 11 F -0.19 -0.25 15.33 2.25 0.03 -0.22 16 12 C -0.69 2.24 4.79 37.16 0.18 2.42 16 13 S 2.59 0.40 4.17 -107.50 -0.45 -0.05 16 14 O -0.90 -1.88 15.64 -67.04 -1.05 -2.92 16 15 O -0.93 -2.29 13.92 -67.04 -0.93 -3.22 16 16 O -0.66 0.37 9.03 -51.82 -0.47 -0.10 16 17 C 0.11 0.00 4.73 -39.23 -0.19 -0.19 16 18 C -0.07 -0.09 4.69 -104.46 -0.49 -0.58 16 19 C -0.10 -0.13 2.19 36.01 0.08 -0.05 16 20 O -0.53 -0.57 12.65 -35.23 -0.45 -1.01 16 21 Si 0.76 -0.12 30.40 -169.99 -5.17 -5.29 16 22 C -0.07 -0.05 8.44 -39.58 -0.33 -0.38 16 23 C -0.05 -0.03 6.33 -39.42 -0.25 -0.28 16 24 Cl -0.02 -0.01 28.61 -51.86 -1.48 -1.50 16 25 C 0.14 -0.03 7.27 -39.41 -0.29 -0.32 16 26 F -0.11 -0.02 16.83 2.25 0.04 0.02 16 27 C -0.15 0.26 8.45 -39.38 -0.33 -0.07 16 28 C -0.17 0.28 4.31 -26.75 -0.12 0.16 16 29 C -0.11 0.14 5.01 -26.75 -0.13 0.01 16 30 H 0.08 -0.24 8.14 -51.92 -0.42 -0.66 16 31 H 0.07 -0.12 8.14 -51.93 -0.42 -0.55 16 32 H 0.07 -0.12 8.14 -51.93 -0.42 -0.54 16 33 H 0.07 0.02 8.13 -51.93 -0.42 -0.40 16 34 H 0.07 0.01 8.13 -51.93 -0.42 -0.41 16 35 H 0.08 0.05 7.76 -51.92 -0.40 -0.35 16 36 H 0.09 -0.11 8.10 -51.93 -0.42 -0.53 16 37 H 0.09 -0.32 8.14 -51.93 -0.42 -0.75 16 38 H 0.09 -0.49 8.14 -51.93 -0.42 -0.91 16 39 H 0.15 -0.73 6.62 -51.92 -0.34 -1.07 16 40 H 0.16 -1.12 8.14 -51.92 -0.42 -1.54 16 41 H 0.09 0.12 5.40 -51.93 -0.28 -0.16 16 42 H 0.37 -0.40 8.59 45.56 0.39 -0.01 16 43 H -0.24 -0.19 6.81 56.52 0.38 0.20 16 44 H -0.24 -0.25 7.11 56.52 0.40 0.15 16 45 H 0.16 -0.02 4.93 -52.49 -0.26 -0.28 16 46 H 0.17 -0.90 7.51 -52.49 -0.39 -1.29 16 47 H 0.11 -0.42 8.14 -51.93 -0.42 -0.84 16 48 H 0.09 -0.05 5.40 -51.93 -0.28 -0.33 16 49 H 0.08 -0.02 7.80 -51.93 -0.41 -0.43 16 50 H 0.09 -0.19 8.11 -51.93 -0.42 -0.61 16 LS Contribution 430.82 15.07 6.49 6.49 Total: 0.00 -8.98 430.82 -11.95 -20.93 By element: Atomic # 1 Polarization: -5.89 SS G_CDS: -6.26 Total: -12.15 kcal Atomic # 6 Polarization: 4.07 SS G_CDS: -1.57 Total: 2.50 kcal Atomic # 8 Polarization: -7.15 SS G_CDS: -3.59 Total: -10.74 kcal Atomic # 9 Polarization: -0.27 SS G_CDS: 0.07 Total: -0.20 kcal Atomic # 14 Polarization: -0.12 SS G_CDS: -5.17 Total: -5.29 kcal Atomic # 16 Polarization: 0.40 SS G_CDS: -0.45 Total: -0.05 kcal Atomic # 17 Polarization: -0.01 SS G_CDS: -1.48 Total: -1.50 kcal Total LS contribution 6.49 Total: 6.49 kcal Total: -8.98 -11.95 -20.93 kcal The number of atoms in the molecule is 50 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. s_40_10548610_16464698.mol2 50 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 -264.248 kcal (2) G-P(sol) polarization free energy of solvation -8.977 kcal (3) G-ENP(sol) elect.-nuc.-pol. free energy of system -273.226 kcal (4) G-CDS(sol) cavity-dispersion-solvent structure free energy -11.949 kcal (5) G-P-CDS(sol) = G-P(sol) + G-CDS(sol) = (2) + (4) -20.927 kcal (6) G-S(sol) free energy of system = (1) + (5) -285.175 kcal 1SCF WAS SPECIFIED, SO GEOMETRY OPTIMIZATION WAS NOT USED Total computer time = 1.66 seconds