Wall clock time and date at job start Sat Apr 11 2020 06:10:03 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 O 1.42908 * 1 3 3 C 1.42893 * 113.99829 * 2 1 4 4 C 1.52997 * 109.47423 * 180.02562 * 3 2 1 5 5 C 1.52990 * 109.47612 * 179.97438 * 4 3 2 6 6 C 1.53006 * 109.47323 * 179.97438 * 5 4 3 7 7 C 1.50697 * 109.47013 * 179.97438 * 6 5 4 8 8 O 1.21282 * 120.00405 * 359.97438 * 7 6 5 9 9 N 1.34780 * 119.99603 * 180.02562 * 7 6 5 10 10 C 1.47160 * 121.08445 * 0.02562 * 9 7 6 11 11 C 1.53283 * 108.57147 * 231.21835 * 10 9 7 12 12 H 1.08994 * 109.51287 * 66.96608 * 11 10 9 13 13 C 1.53002 * 109.51200 * 187.07196 * 11 10 9 14 14 O 1.43126 * 109.21945 * 306.99303 * 11 10 9 15 15 C 1.41887 * 114.37422 * 60.89331 * 14 11 10 16 16 C 1.54357 * 110.75391 * 176.66968 * 15 14 11 17 17 C 1.54467 * 102.96294 * 276.10529 * 16 15 14 18 18 N 1.47087 * 107.29257 * 338.89887 * 17 16 15 19 19 C 1.36931 * 125.63639 * 178.84946 * 18 17 16 20 20 H 1.07999 * 120.00836 * 186.33582 * 19 18 17 21 21 C 1.38817 * 119.99862 * 6.34514 * 19 18 17 22 22 N 1.31625 * 119.99829 * 7.37839 * 21 19 18 23 23 Si 1.86795 * 120.00129 * 187.11038 * 21 19 18 24 24 H 1.48504 * 109.46958 * 265.28785 * 23 21 19 25 25 H 1.48489 * 109.47308 * 25.28591 * 23 21 19 26 26 H 1.48496 * 109.47352 * 145.29218 * 23 21 19 27 27 C 1.47572 * 108.73802 * 358.58570 * 18 17 16 28 28 C 1.47338 * 121.07614 * 180.02562 * 9 7 6 29 29 H 1.08996 * 109.47010 * 299.99755 * 1 2 3 30 30 H 1.09000 * 109.47400 * 59.99672 * 1 2 3 31 31 H 1.09003 * 109.46845 * 179.97438 * 1 2 3 32 32 H 1.09002 * 109.47334 * 60.00112 * 3 2 1 33 33 H 1.09007 * 109.47383 * 299.99969 * 3 2 1 34 34 H 1.09002 * 109.47156 * 59.99535 * 4 3 2 35 35 H 1.08998 * 109.46543 * 300.00294 * 4 3 2 36 36 H 1.09002 * 109.47203 * 59.99610 * 5 4 3 37 37 H 1.08998 * 109.47444 * 299.99788 * 5 4 3 38 38 H 1.08995 * 109.46742 * 60.00095 * 6 5 4 39 39 H 1.08998 * 109.46953 * 300.00415 * 6 5 4 40 40 H 1.09003 * 109.61690 * 350.93755 * 10 9 7 41 41 H 1.09002 * 109.62293 * 111.30362 * 10 9 7 42 42 H 1.09000 * 109.47487 * 59.99591 * 13 11 10 43 43 H 1.09002 * 109.46784 * 179.97438 * 13 11 10 44 44 H 1.08995 * 109.47128 * 299.99812 * 13 11 10 45 45 H 1.09000 * 110.72734 * 34.67785 * 16 15 14 46 46 H 1.09001 * 110.72930 * 157.79964 * 16 15 14 47 47 H 1.09002 * 110.00266 * 219.40622 * 17 16 15 48 48 H 1.08998 * 109.76069 * 98.25229 * 17 16 15 49 49 H 0.96994 * 119.99763 * 179.73061 * 22 21 19 50 50 H 1.08997 * 110.37722 * 142.40310 * 27 18 17 51 51 H 1.08998 * 110.38205 * 264.64975 * 27 18 17 52 52 H 1.08996 * 109.68245 * 11.11148 * 28 9 7 53 53 H 1.09003 * 109.67283 * 250.57054 * 28 9 7 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 8 1.4291 0.0000 0.0000 3 6 2.0102 1.3054 0.0000 4 6 3.5354 1.1847 -0.0006 5 6 4.1577 2.5824 -0.0013 6 6 5.6830 2.4616 -0.0013 7 6 6.2959 3.8383 -0.0026 8 8 5.5830 4.8195 -0.0039 9 7 7.6363 3.9792 -0.0033 10 6 8.5236 2.8052 -0.0035 11 6 9.5446 2.9648 1.1286 12 1 9.0338 2.9108 2.0899 13 6 10.5855 1.8469 1.0395 14 8 10.1941 4.2339 1.0019 15 6 9.3216 5.3495 1.0887 16 6 10.1160 6.6714 1.0252 17 6 10.5665 6.8756 2.4885 18 7 9.6663 6.0810 3.3381 19 6 9.7436 5.9737 4.7010 20 1 9.0990 5.2843 5.2259 21 6 10.6505 6.7513 5.4080 22 7 11.3320 7.6929 4.7904 23 14 10.8980 6.4664 7.2375 24 1 10.0325 7.3976 8.0050 25 1 10.5381 5.0656 7.5735 26 1 12.3202 6.7099 7.5884 27 6 8.6620 5.4235 2.4797 28 6 8.2608 5.3137 -0.0040 29 1 -0.3633 0.5138 0.8900 30 1 -0.3634 0.5139 -0.8899 31 1 -0.3633 -1.0277 -0.0005 32 1 1.6886 1.8464 0.8900 33 1 1.6886 1.8464 -0.8900 34 1 3.8568 0.6439 -0.8908 35 1 3.8574 0.6436 0.8891 36 1 3.8364 3.1236 0.8887 37 1 3.8358 3.1231 -0.8913 38 1 6.0045 1.9203 -0.8910 39 1 6.0046 1.9210 0.8889 40 1 7.9355 1.9019 0.1588 41 1 9.0414 2.7378 -0.9603 42 1 11.0972 1.9026 0.0787 43 1 11.3114 1.9614 1.8445 44 1 10.0896 0.8807 1.1315 45 1 10.9768 6.5728 0.3638 46 1 9.4749 7.4916 0.7022 47 1 10.4951 7.9296 2.7570 48 1 11.5927 6.5289 2.6100 49 1 11.9628 8.2388 5.2853 50 1 8.4436 4.4219 2.8499 51 1 7.7501 6.0191 2.4378 52 1 7.5043 6.0730 0.1940 53 1 8.7250 5.5011 -0.9722 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 ZINC001131642635.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 06:10:03 Heat of formation + Delta-G solvation = -102.359009 kcal Electronic energy + Delta-G solvation = -31190.560247 eV Core-core repulsion = 27063.159368 eV Total energy + Delta-G solvation = -4127.400878 eV No. of doubly occupied orbitals = 66 Molecular weight (most abundant/longest-lived isotopes) = 340.220 amu Computer time = 1.29 seconds Orbital eigenvalues (eV) -40.61738 -38.90873 -38.25986 -36.33703 -35.03844 -34.57657 -33.14603 -31.31997 -30.49847 -29.34059 -28.29440 -26.89547 -26.49402 -25.64807 -24.33874 -23.18569 -21.87320 -21.46551 -20.18140 -19.61974 -18.78090 -17.21601 -16.96858 -16.72388 -16.67661 -16.40898 -15.94993 -15.76185 -15.22307 -14.85865 -14.60986 -14.51776 -14.16825 -13.88551 -13.59126 -13.45976 -13.22767 -12.90629 -12.71760 -12.45325 -12.27949 -12.13988 -12.01515 -11.90829 -11.81129 -11.75456 -11.62793 -11.49288 -11.22512 -11.03544 -10.92358 -10.90454 -10.79289 -10.42889 -10.25392 -10.12446 -10.06867 -10.01400 -9.65636 -9.64033 -9.51342 -8.57786 -8.33882 -6.76994 -5.67138 -3.01662 2.61323 2.85644 3.40849 3.41735 3.46780 3.49027 3.87417 4.38316 4.51561 4.57876 4.61117 4.69796 4.86618 4.91037 4.93180 5.00314 5.02140 5.08014 5.09389 5.13867 5.21455 5.27755 5.31479 5.40459 5.42844 5.46411 5.47619 5.55492 5.62151 5.62249 5.62894 5.72283 5.88513 5.92279 5.95433 6.05736 6.06938 6.19058 6.19428 6.33415 6.43013 6.49998 6.63236 6.67995 6.80120 7.35676 7.54488 7.64293 7.73015 7.84679 8.14772 8.29602 9.24327 9.84989 10.51587 11.43380 Molecular weight = 340.22amu Principal moments of inertia in cm(-1) A = 0.012451 B = 0.002539 C = 0.002349 Principal moments of inertia in units of 10**(-40)*gram-cm**2 A = 2248.261576 B =11023.243725 C =11916.282198 Net atomic charges, atomic populations, and dipole contributions calculated with CM2 Atom NO. Type Charge No. of electrons 1 C 0.032 3.968 2 O -0.395 6.395 3 C 0.060 3.940 4 C -0.118 4.118 5 C -0.102 4.102 6 C -0.138 4.138 7 C 0.515 3.485 8 O -0.540 6.540 9 N -0.614 5.614 10 C 0.079 3.921 11 C 0.069 3.931 12 H 0.068 0.932 13 C -0.141 4.141 14 O -0.347 6.347 15 C 0.092 3.908 16 C -0.128 4.128 17 C 0.178 3.822 18 N -0.597 5.597 19 C -0.226 4.226 20 H 0.074 0.926 21 C -0.008 4.008 22 N -0.919 5.919 23 Si 0.911 3.089 24 H -0.289 1.289 25 H -0.282 1.282 26 H -0.290 1.290 27 C 0.121 3.879 28 C 0.098 3.902 29 H 0.041 0.959 30 H 0.040 0.960 31 H 0.085 0.915 32 H 0.051 0.949 33 H 0.050 0.950 34 H 0.071 0.929 35 H 0.072 0.928 36 H 0.073 0.927 37 H 0.072 0.928 38 H 0.093 0.907 39 H 0.095 0.905 40 H 0.090 0.910 41 H 0.076 0.924 42 H 0.062 0.938 43 H 0.070 0.930 44 H 0.069 0.931 45 H 0.072 0.928 46 H 0.074 0.926 47 H 0.061 0.939 48 H 0.034 0.966 49 H 0.252 0.748 50 H 0.038 0.962 51 H 0.025 0.975 52 H 0.101 0.899 53 H 0.071 0.929 For the charges calculated by CM2: Dipole moment (debyes) X Y Z Total from point charges -12.488 -14.847 -14.332 24.120 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 -0.065 4.065 2 O -0.314 6.314 3 C -0.017 4.017 4 C -0.156 4.156 5 C -0.140 4.140 6 C -0.178 4.178 7 C 0.304 3.696 8 O -0.417 6.417 9 N -0.347 5.347 10 C -0.045 4.045 11 C 0.011 3.989 12 H 0.086 0.914 13 C -0.198 4.198 14 O -0.266 6.266 15 C 0.051 3.949 16 C -0.167 4.167 17 C 0.053 3.947 18 N -0.323 5.323 19 C -0.354 4.354 20 H 0.092 0.908 21 C -0.204 4.204 22 N -0.566 5.566 23 Si 0.741 3.259 24 H -0.217 1.217 25 H -0.207 1.207 26 H -0.216 1.216 27 C -0.006 4.006 28 C -0.025 4.025 29 H 0.060 0.940 30 H 0.059 0.941 31 H 0.103 0.897 32 H 0.069 0.931 33 H 0.068 0.932 34 H 0.089 0.911 35 H 0.091 0.909 36 H 0.092 0.908 37 H 0.090 0.910 38 H 0.111 0.889 39 H 0.113 0.887 40 H 0.109 0.891 41 H 0.094 0.906 42 H 0.081 0.919 43 H 0.090 0.910 44 H 0.087 0.913 45 H 0.091 0.909 46 H 0.092 0.908 47 H 0.079 0.921 48 H 0.052 0.948 49 H 0.062 0.938 50 H 0.056 0.944 51 H 0.042 0.958 52 H 0.120 0.880 53 H 0.089 0.911 Dipole moment (debyes) X Y Z Total from point charges -12.440 -14.367 -14.181 23.712 hybrid contribution -0.227 0.044 1.026 1.052 sum -12.666 -14.322 -13.155 23.208 Atomic orbital electron populations 1.22737 0.81025 1.02698 1.00046 1.87858 1.19741 1.28334 1.95463 1.22567 0.94202 0.84445 1.00465 1.21527 0.93047 0.97589 1.03428 1.21243 0.92788 0.95954 1.04006 1.21668 0.96850 0.94858 1.04399 1.20661 0.81452 0.91747 0.75746 1.90698 1.60253 1.40887 1.49855 1.48236 1.05467 1.07518 1.73508 1.22535 0.93045 0.88435 1.00461 1.22441 0.93621 0.85697 0.97162 0.91380 1.21686 0.98936 0.95784 1.03409 1.87842 1.33403 1.12257 1.93119 1.22317 0.90226 0.87902 0.94474 1.22820 0.99438 0.92909 1.01533 1.21203 0.93216 0.96908 0.83323 1.44415 1.30711 1.54950 1.02265 1.18999 1.17720 1.18094 0.80585 0.90774 1.24791 0.99800 0.97802 0.98052 1.69950 1.29756 1.22432 1.34510 0.86117 0.77179 0.77590 0.84977 1.21679 1.20738 1.21635 1.21920 0.92582 0.96511 0.89558 1.22162 0.96390 0.84756 0.99200 0.94016 0.94099 0.89671 0.93077 0.93210 0.91053 0.90905 0.90778 0.90966 0.88867 0.88684 0.89128 0.90576 0.91875 0.91047 0.91255 0.90937 0.90795 0.92131 0.94778 0.93792 0.94408 0.95779 0.88031 0.91091 Number of geometries 1 Number of calculations of the screened coulomb radii 1 The total number of SCF iterations 17. 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 0.03 0.21 11.01 101.05 1.11 1.32 16 2 O -0.39 -3.78 10.70 -35.23 -0.38 -4.16 16 3 C 0.06 0.50 5.94 37.16 0.22 0.72 16 4 C -0.12 -0.94 5.58 -26.74 -0.15 -1.08 16 5 C -0.10 -0.94 4.50 -26.73 -0.12 -1.06 16 6 C -0.14 -1.27 4.07 -27.88 -0.11 -1.38 16 7 C 0.52 7.02 7.71 -10.99 -0.08 6.93 16 8 O -0.54 -9.33 15.47 5.56 0.09 -9.24 16 9 N -0.61 -8.29 2.96 -172.70 -0.51 -8.80 16 10 C 0.08 0.85 5.81 -3.54 -0.02 0.83 16 11 C 0.07 0.96 3.20 -26.58 -0.08 0.87 16 12 H 0.07 1.06 6.25 -51.93 -0.32 0.74 16 13 C -0.14 -1.54 9.57 37.16 0.36 -1.19 16 14 O -0.35 -6.21 9.92 -35.22 -0.35 -6.56 16 15 C 0.09 1.68 0.84 -89.66 -0.07 1.60 16 16 C -0.13 -2.45 6.12 -25.25 -0.15 -2.61 16 17 C 0.18 4.43 5.44 -2.95 -0.02 4.42 16 18 N -0.60 -15.73 3.40 -170.31 -0.58 -16.31 16 19 C -0.23 -6.46 10.26 -15.06 -0.15 -6.61 16 20 H 0.07 2.06 7.84 -52.49 -0.41 1.65 16 21 C -0.01 -0.23 5.45 -17.43 -0.09 -0.33 16 22 N -0.92 -27.43 10.47 55.49 0.58 -26.85 16 23 Si 0.91 22.51 29.56 -169.99 -5.02 17.49 16 24 H -0.29 -7.14 7.11 56.52 0.40 -6.73 16 25 H -0.28 -6.78 7.11 56.52 0.40 -6.38 16 26 H -0.29 -7.20 7.11 56.52 0.40 -6.80 16 27 C 0.12 2.64 6.18 -2.87 -0.02 2.62 16 28 C 0.10 1.51 5.29 -3.92 -0.02 1.49 16 29 H 0.04 0.24 8.14 -51.93 -0.42 -0.18 16 30 H 0.04 0.23 8.14 -51.93 -0.42 -0.19 16 31 H 0.08 0.44 8.14 -51.93 -0.42 0.02 16 32 H 0.05 0.41 8.14 -51.93 -0.42 -0.01 16 33 H 0.05 0.38 8.14 -51.92 -0.42 -0.04 16 34 H 0.07 0.53 8.14 -51.93 -0.42 0.10 16 35 H 0.07 0.57 8.14 -51.93 -0.42 0.15 16 36 H 0.07 0.78 8.10 -51.93 -0.42 0.36 16 37 H 0.07 0.71 8.10 -51.93 -0.42 0.28 16 38 H 0.09 0.65 8.00 -51.93 -0.42 0.24 16 39 H 0.09 0.76 7.67 -51.93 -0.40 0.37 16 40 H 0.09 0.71 6.05 -51.93 -0.31 0.39 16 41 H 0.08 0.74 8.14 -51.93 -0.42 0.32 16 42 H 0.06 0.64 8.14 -51.93 -0.42 0.21 16 43 H 0.07 0.90 8.14 -51.93 -0.42 0.48 16 44 H 0.07 0.56 8.14 -51.93 -0.42 0.14 16 45 H 0.07 1.27 8.14 -51.93 -0.42 0.85 16 46 H 0.07 1.29 7.99 -51.93 -0.42 0.87 16 47 H 0.06 1.66 6.99 -51.93 -0.36 1.30 16 48 H 0.03 0.93 7.92 -51.93 -0.41 0.52 16 49 H 0.25 7.28 8.31 -40.82 -0.34 6.94 16 50 H 0.04 0.82 6.09 -51.93 -0.32 0.51 16 51 H 0.02 0.56 7.82 -51.93 -0.41 0.15 16 52 H 0.10 1.71 6.86 -51.93 -0.36 1.35 16 53 H 0.07 0.99 8.14 -51.93 -0.42 0.57 16 LS Contribution 410.64 15.07 6.19 6.19 Total: -1.00 -34.53 410.64 -9.01 -43.54 By element: Atomic # 1 Polarization: 7.78 SS G_CDS: -9.60 Total: -1.83 kcal Atomic # 6 Polarization: 5.95 SS G_CDS: 0.58 Total: 6.53 kcal Atomic # 7 Polarization: -51.45 SS G_CDS: -0.51 Total: -51.96 kcal Atomic # 8 Polarization: -19.32 SS G_CDS: -0.64 Total: -19.96 kcal Atomic # 14 Polarization: 22.51 SS G_CDS: -5.02 Total: 17.49 kcal Total LS contribution 6.19 Total: 6.19 kcal Total: -34.53 -9.01 -43.54 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. ZINC001131642635.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 -58.820 kcal (2) G-P(sol) polarization free energy of solvation -34.531 kcal (3) G-ENP(sol) elect.-nuc.-pol. free energy of system -93.351 kcal (4) G-CDS(sol) cavity-dispersion-solvent structure free energy -9.008 kcal (5) G-P-CDS(sol) = G-P(sol) + G-CDS(sol) = (2) + (4) -43.540 kcal (6) G-S(sol) free energy of system = (1) + (5) -102.359 kcal 1SCF WAS SPECIFIED, SO GEOMETRY OPTIMIZATION WAS NOT USED Total computer time = 1.29 seconds