Wall clock time and date at job start Sat Apr 11 2020 06:10:14 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 1.53005 * 1 3 3 H 1.09001 * 109.44853 * 2 1 4 4 C 1.53028 * 109.46428 * 119.97300 * 2 1 3 5 5 C 1.53118 * 109.28015 * 179.19583 * 4 2 1 6 6 H 1.08997 * 109.57539 * 62.28352 * 5 4 2 7 7 N 1.46504 * 109.52494 * 182.43936 * 5 4 2 8 8 C 1.34774 * 120.00416 * 204.68337 * 7 5 4 9 9 O 1.21284 * 119.99822 * 0.02562 * 8 7 5 10 10 C 1.50698 * 120.00195 * 180.27985 * 8 7 5 11 11 S 1.81002 * 109.46966 * 179.72427 * 10 8 7 12 12 C 1.76200 * 99.99907 * 179.97438 * 11 10 8 13 13 H 1.08001 * 119.99799 * 0.02562 * 12 11 10 14 14 C 1.38803 * 119.99985 * 179.97438 * 12 11 10 15 15 N 1.31623 * 120.00023 * 0.02562 * 14 12 11 16 16 Si 1.86801 * 119.99921 * 179.97438 * 14 12 11 17 17 H 1.48503 * 109.46774 * 60.00616 * 16 14 12 18 18 H 1.48496 * 109.47134 * 179.97438 * 16 14 12 19 19 H 1.48496 * 109.47236 * 300.00650 * 16 14 12 20 20 C 1.53111 * 109.16151 * 302.34577 * 5 4 2 21 21 C 1.53040 * 109.27986 * 57.65258 * 20 5 4 22 22 N 1.46843 * 109.46218 * 240.03108 * 2 1 3 23 23 C 1.46897 * 111.00300 * 54.14156 * 22 2 1 24 24 C 1.53003 * 109.47220 * 202.21890 * 23 22 2 25 25 C 1.54262 * 110.03452 * 289.67523 * 24 23 22 26 26 C 1.54888 * 104.19720 * 217.10533 * 25 24 23 27 27 C 1.54883 * 102.74612 * 37.93886 * 26 25 24 28 28 C 1.53869 * 110.03444 * 172.50383 * 24 23 22 29 29 H 1.08999 * 109.47135 * 172.11415 * 1 2 3 30 30 H 1.08998 * 109.47097 * 292.11056 * 1 2 3 31 31 H 1.09001 * 109.47199 * 52.10896 * 1 2 3 32 32 H 1.09002 * 109.50799 * 59.25200 * 4 2 1 33 33 H 1.09006 * 109.50807 * 299.13830 * 4 2 1 34 34 H 0.97007 * 119.99651 * 24.68515 * 7 5 4 35 35 H 1.09003 * 109.46906 * 299.72106 * 10 8 7 36 36 H 1.08994 * 109.47211 * 59.72461 * 10 8 7 37 37 H 0.97002 * 120.00259 * 179.97438 * 15 14 12 38 38 H 1.09003 * 109.50841 * 177.59220 * 20 5 4 39 39 H 1.09005 * 109.50588 * 297.71064 * 20 5 4 40 40 H 1.09002 * 109.45725 * 60.83380 * 21 20 5 41 41 H 1.08997 * 109.46752 * 180.80590 * 21 20 5 42 42 H 1.08996 * 109.47240 * 322.21826 * 23 22 2 43 43 H 1.09002 * 109.47121 * 82.22018 * 23 22 2 44 44 H 1.09006 * 110.01462 * 51.11649 * 24 23 22 45 45 H 1.08999 * 110.48532 * 335.78414 * 25 24 23 46 46 H 1.09000 * 110.49146 * 98.42378 * 25 24 23 47 47 H 1.08997 * 110.75387 * 279.62626 * 26 25 24 48 48 H 1.08999 * 110.91657 * 156.32835 * 26 25 24 49 49 H 1.09004 * 110.48349 * 203.37603 * 27 26 25 50 50 H 1.09002 * 110.59912 * 80.79401 * 27 26 25 51 51 H 1.08995 * 110.03993 * 238.57305 * 28 24 23 52 52 H 1.09005 * 110.03262 * 0.02562 * 28 24 23 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 1 1.8930 1.0278 0.0000 4 6 2.0400 -0.7208 1.2499 5 6 3.5710 -0.7360 1.2355 6 1 3.9466 0.2867 1.2677 7 7 4.0643 -1.4755 2.4000 8 6 5.2962 -1.2244 2.8855 9 8 5.9963 -0.3857 2.3587 10 6 5.8060 -1.9895 4.0795 11 16 7.4811 -1.4341 4.4818 12 6 7.8188 -2.4624 5.8721 13 1 7.0751 -3.1656 6.2170 14 6 9.0410 -2.3696 6.5234 15 7 9.9475 -1.5130 6.1027 16 14 9.3988 -3.4593 7.9978 17 1 9.3165 -4.8851 7.5910 18 1 10.7625 -3.1688 8.5088 19 1 8.4020 -3.1908 9.0653 20 6 4.0548 -1.4187 -0.0467 21 6 3.4865 -0.6776 -1.2591 22 7 2.0193 -0.6916 -1.1994 23 6 1.4373 -0.1104 -2.4165 24 6 1.4981 -1.1356 -3.5507 25 6 2.9591 -1.3373 -4.0030 26 6 2.8600 -1.5183 -5.5381 27 6 1.7462 -0.5155 -5.9292 28 6 0.7269 -0.6132 -4.7754 29 1 -0.3633 -1.0179 -0.1410 30 1 -0.3633 0.3868 0.9521 31 1 -0.3633 0.6312 -0.8110 32 1 1.6660 -1.7446 1.2576 33 1 1.6896 -0.1981 2.1399 34 1 3.5042 -2.1460 2.8216 35 1 5.1500 -1.8123 4.9318 36 1 5.8220 -3.0546 3.8487 37 1 10.8015 -1.4478 6.5581 38 1 5.1440 -1.3945 -0.0833 39 1 3.7126 -2.4535 -0.0595 40 1 3.8403 0.3534 -1.2532 41 1 3.8175 -1.1697 -2.1736 42 1 0.3988 0.1620 -2.2284 43 1 2.0006 0.7787 -2.6999 44 1 1.0747 -2.0839 -3.2195 45 1 3.5582 -0.4597 -3.7602 46 1 3.3821 -2.2289 -3.5403 47 1 2.5672 -2.5378 -5.7887 48 1 3.8013 -1.2582 -6.0221 49 1 1.2841 -0.8074 -6.8723 50 1 2.1477 0.4955 -5.9990 51 1 -0.0702 -1.3082 -5.0392 52 1 0.3097 0.3710 -4.5620 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 ZINC001724988735.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 06:10:14 Heat of formation + Delta-G solvation = -53.408785 kcal Electronic energy + Delta-G solvation = -27592.896622 eV Core-core repulsion = 23910.371256 eV Total energy + Delta-G solvation = -3682.525366 eV No. of doubly occupied orbitals = 63 Molecular weight (most abundant/longest-lived isotopes) = 340.193 amu Computer time = 1.59 seconds Orbital eigenvalues (eV) -40.30431 -39.07861 -37.86092 -34.98345 -32.79178 -32.41771 -32.13015 -29.90646 -28.98166 -28.45375 -27.28165 -25.50649 -24.98391 -22.79908 -21.77665 -20.87337 -20.30926 -19.99224 -19.61980 -17.81351 -16.69910 -16.27842 -16.07444 -15.85164 -15.57756 -15.17119 -14.85169 -14.79150 -14.45571 -14.06736 -13.94746 -13.70994 -13.44763 -13.22680 -13.13082 -12.76960 -12.55391 -12.35843 -12.28073 -12.13474 -11.88283 -11.75063 -11.44855 -11.31415 -11.24862 -11.07319 -11.03121 -11.02701 -10.94825 -10.90873 -10.77067 -10.65055 -10.48376 -10.42022 -9.80427 -9.32488 -9.04954 -8.80513 -8.52307 -8.22155 -6.48320 -6.20212 -3.90629 3.05830 3.13577 3.24398 3.28440 3.32468 3.56817 3.74192 4.21973 4.26465 4.32408 4.43011 4.53186 4.65948 4.73847 4.92984 4.98154 5.03785 5.08717 5.11988 5.14774 5.19306 5.22773 5.27726 5.30997 5.32750 5.37484 5.40322 5.45674 5.46838 5.53402 5.59202 5.63768 5.67143 5.69136 5.73700 5.79083 5.81739 5.86257 5.91162 5.92054 5.99329 6.00838 6.09361 6.15936 6.16725 6.27169 6.72249 6.90391 6.92220 7.60562 7.77854 8.36368 8.66645 9.24905 10.87142 Molecular weight = 340.19amu Principal moments of inertia in cm(-1) A = 0.023500 B = 0.001893 C = 0.001803 Principal moments of inertia in units of 10**(-40)*gram-cm**2 A = 1191.227715 B =14785.637930 C =15522.995854 Net atomic charges, atomic populations, and dipole contributions calculated with CM2 Atom NO. Type Charge No. of electrons 1 C -0.147 4.147 2 C 0.085 3.915 3 H 0.041 0.959 4 C -0.117 4.117 5 C 0.147 3.853 6 H 0.082 0.918 7 N -0.734 5.734 8 C 0.533 3.467 9 O -0.519 6.519 10 C -0.154 4.154 11 S -0.060 6.060 12 C -0.536 4.536 13 H 0.072 0.928 14 C 0.073 3.927 15 N -0.868 5.868 16 Si 0.919 3.081 17 H -0.274 1.274 18 H -0.283 1.283 19 H -0.274 1.274 20 C -0.127 4.127 21 C 0.042 3.958 22 N -0.531 5.531 23 C 0.054 3.946 24 C -0.084 4.084 25 C -0.122 4.122 26 C -0.128 4.128 27 C -0.125 4.125 28 C -0.120 4.120 29 H 0.066 0.934 30 H 0.061 0.939 31 H 0.056 0.944 32 H 0.076 0.924 33 H 0.072 0.928 34 H 0.397 0.603 35 H 0.089 0.911 36 H 0.089 0.911 37 H 0.269 0.731 38 H 0.074 0.926 39 H 0.071 0.929 40 H 0.033 0.967 41 H 0.095 0.905 42 H 0.079 0.921 43 H 0.035 0.965 44 H 0.080 0.920 45 H 0.067 0.933 46 H 0.070 0.930 47 H 0.065 0.935 48 H 0.064 0.936 49 H 0.062 0.938 50 H 0.063 0.937 51 H 0.063 0.937 52 H 0.062 0.938 For the charges calculated by CM2: Dipole moment (debyes) X Y Z Total from point charges -22.681 0.948 -20.692 30.716 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 -0.205 4.205 2 C -0.024 4.024 3 H 0.059 0.941 4 C -0.155 4.155 5 C 0.041 3.959 6 H 0.100 0.900 7 N -0.387 5.387 8 C 0.319 3.681 9 O -0.393 6.393 10 C -0.304 4.304 11 S 0.166 5.834 12 C -0.684 4.684 13 H 0.090 0.910 14 C -0.136 4.136 15 N -0.503 5.503 16 Si 0.745 3.255 17 H -0.199 1.199 18 H -0.208 1.208 19 H -0.199 1.199 20 C -0.166 4.166 21 C -0.086 4.086 22 N -0.256 5.256 23 C -0.074 4.074 24 C -0.103 4.103 25 C -0.160 4.160 26 C -0.165 4.165 27 C -0.163 4.163 28 C -0.158 4.158 29 H 0.085 0.915 30 H 0.080 0.920 31 H 0.075 0.925 32 H 0.095 0.905 33 H 0.091 0.909 34 H 0.231 0.769 35 H 0.107 0.893 36 H 0.107 0.893 37 H 0.079 0.921 38 H 0.093 0.907 39 H 0.090 0.910 40 H 0.051 0.949 41 H 0.113 0.887 42 H 0.097 0.903 43 H 0.053 0.947 44 H 0.098 0.902 45 H 0.085 0.915 46 H 0.089 0.911 47 H 0.084 0.916 48 H 0.082 0.918 49 H 0.080 0.920 50 H 0.082 0.918 51 H 0.082 0.918 52 H 0.081 0.919 Dipole moment (debyes) X Y Z Total from point charges -21.465 1.958 -21.490 30.437 hybrid contribution -0.537 -1.144 1.770 2.175 sum -22.002 0.813 -19.720 29.557 Atomic orbital electron populations 1.21934 0.94189 1.02651 1.01685 1.21518 0.95288 0.95545 0.90054 0.94055 1.21893 0.94363 1.02081 0.97156 1.20909 0.93058 0.96744 0.85152 0.89972 1.46071 1.17396 1.42872 1.32402 1.20306 0.80701 0.82768 0.84354 1.90692 1.55760 1.33155 1.59689 1.23536 1.06239 1.02825 0.97826 1.85381 1.06221 1.52811 1.38968 1.22834 1.04050 1.25284 1.16251 0.90994 1.24990 0.95074 0.95796 0.97723 1.70006 1.06350 1.34025 1.39929 0.86227 0.77577 0.80282 0.81432 1.19944 1.20816 1.19949 1.21992 1.01108 1.00157 0.93320 1.22522 0.86814 0.99340 0.99939 1.61980 1.07374 1.54786 1.01456 1.22384 1.00055 0.95312 0.89632 1.21748 0.95570 0.99305 0.93721 1.22654 0.96548 1.01697 0.95067 1.22535 0.98546 0.99303 0.96157 1.22352 0.96460 0.99502 0.97957 1.22183 0.97981 1.01027 0.94643 0.91504 0.92008 0.92519 0.90492 0.90933 0.76906 0.89310 0.89265 0.92146 0.90724 0.91032 0.94913 0.88658 0.90304 0.94679 0.90172 0.91461 0.91140 0.91610 0.91761 0.91968 0.91841 0.91830 0.91940 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 -1.00 8.61 37.16 0.32 -0.68 16 2 C 0.08 0.73 2.44 -67.73 -0.17 0.56 16 3 H 0.04 0.39 8.14 -51.93 -0.42 -0.03 16 4 C -0.12 -1.08 4.84 -26.66 -0.13 -1.21 16 5 C 0.15 1.80 2.52 -67.81 -0.17 1.62 16 6 H 0.08 1.21 7.58 -51.93 -0.39 0.81 16 7 N -0.73 -10.00 5.08 -53.69 -0.27 -10.27 16 8 C 0.53 10.02 7.81 -10.99 -0.09 9.94 16 9 O -0.52 -11.83 15.53 5.55 0.09 -11.75 16 10 C -0.15 -3.13 6.16 36.00 0.22 -2.91 16 11 S -0.06 -1.65 20.57 -107.50 -2.21 -3.87 16 12 C -0.54 -15.38 9.50 30.94 0.29 -15.08 16 13 H 0.07 1.95 7.80 -52.49 -0.41 1.54 16 14 C 0.07 2.11 5.49 -17.43 -0.10 2.01 16 15 N -0.87 -26.32 13.22 55.49 0.73 -25.58 16 16 Si 0.92 21.52 29.55 -169.99 -5.02 16.49 16 17 H -0.27 -6.26 7.11 56.52 0.40 -5.86 16 18 H -0.28 -6.50 7.11 56.52 0.40 -6.10 16 19 H -0.27 -6.26 7.11 56.52 0.40 -5.86 16 20 C -0.13 -1.50 5.67 -26.65 -0.15 -1.65 16 21 C 0.04 0.42 4.83 -3.83 -0.02 0.40 16 22 N -0.53 -4.65 4.40 -226.69 -1.00 -5.64 16 23 C 0.05 0.40 4.20 -3.82 -0.02 0.39 16 24 C -0.08 -0.59 3.13 -89.51 -0.28 -0.87 16 25 C -0.12 -0.89 4.39 -25.08 -0.11 -1.00 16 26 C -0.13 -0.84 6.91 -24.74 -0.17 -1.01 16 27 C -0.13 -0.76 6.83 -25.08 -0.17 -0.93 16 28 C -0.12 -0.73 6.46 -25.62 -0.17 -0.89 16 29 H 0.07 0.47 8.14 -51.93 -0.42 0.05 16 30 H 0.06 0.39 8.13 -51.93 -0.42 -0.04 16 31 H 0.06 0.35 6.34 -51.93 -0.33 0.02 16 32 H 0.08 0.68 8.14 -51.93 -0.42 0.25 16 33 H 0.07 0.64 8.14 -51.93 -0.42 0.22 16 34 H 0.40 4.28 8.60 -40.82 -0.35 3.93 16 35 H 0.09 1.67 8.14 -51.91 -0.42 1.25 16 36 H 0.09 1.68 8.14 -51.92 -0.42 1.26 16 37 H 0.27 7.59 8.31 -40.82 -0.34 7.25 16 38 H 0.07 1.06 8.14 -51.93 -0.42 0.64 16 39 H 0.07 0.82 8.14 -51.93 -0.42 0.40 16 40 H 0.03 0.36 8.14 -51.93 -0.42 -0.07 16 41 H 0.10 0.88 3.86 -51.93 -0.20 0.68 16 42 H 0.08 0.54 5.35 -51.93 -0.28 0.26 16 43 H 0.03 0.28 7.76 -51.93 -0.40 -0.12 16 44 H 0.08 0.63 8.14 -51.93 -0.42 0.21 16 45 H 0.07 0.53 6.56 -51.93 -0.34 0.19 16 46 H 0.07 0.55 7.31 -51.93 -0.38 0.17 16 47 H 0.07 0.42 8.14 -51.93 -0.42 0.00 16 48 H 0.06 0.41 8.14 -51.93 -0.42 -0.01 16 49 H 0.06 0.34 8.14 -51.93 -0.42 -0.08 16 50 H 0.06 0.39 8.14 -51.93 -0.42 -0.04 16 51 H 0.06 0.36 8.14 -51.93 -0.42 -0.06 16 52 H 0.06 0.36 7.67 -51.93 -0.40 -0.04 16 LS Contribution 406.90 15.07 6.13 6.13 Total: -1.00 -33.15 406.90 -11.83 -44.99 By element: Atomic # 1 Polarization: 10.19 SS G_CDS: -9.38 Total: 0.81 kcal Atomic # 6 Polarization: -10.41 SS G_CDS: -0.90 Total: -11.30 kcal Atomic # 7 Polarization: -40.96 SS G_CDS: -0.54 Total: -41.50 kcal Atomic # 8 Polarization: -11.83 SS G_CDS: 0.09 Total: -11.75 kcal Atomic # 14 Polarization: 21.52 SS G_CDS: -5.02 Total: 16.49 kcal Atomic # 16 Polarization: -1.65 SS G_CDS: -2.21 Total: -3.87 kcal Total LS contribution 6.13 Total: 6.13 kcal Total: -33.15 -11.83 -44.99 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. ZINC001724988735.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 -8.423 kcal (2) G-P(sol) polarization free energy of solvation -33.153 kcal (3) G-ENP(sol) elect.-nuc.-pol. free energy of system -41.576 kcal (4) G-CDS(sol) cavity-dispersion-solvent structure free energy -11.833 kcal (5) G-P-CDS(sol) = G-P(sol) + G-CDS(sol) = (2) + (4) -44.986 kcal (6) G-S(sol) free energy of system = (1) + (5) -53.409 kcal 1SCF WAS SPECIFIED, SO GEOMETRY OPTIMIZATION WAS NOT USED Total computer time = 1.59 seconds