Wall clock time and date at job start Wed Apr 1 2020 00:20:00 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 1.42901 * 1 3 3 C 1.42900 * 113.99476 * 2 1 4 4 C 1.53001 * 109.46968 * 180.02562 * 3 2 1 5 5 C 1.52994 * 109.47496 * 59.99677 * 4 3 2 6 6 C 1.53007 * 109.46863 * 299.99610 * 4 3 2 7 7 C 1.50696 * 109.47238 * 180.02562 * 4 3 2 8 8 O 1.21289 * 120.00063 * 8.53830 * 7 4 3 9 9 N 1.34772 * 120.00036 * 188.54132 * 7 4 3 10 10 C 1.47188 * 121.06091 * 354.32328 * 9 7 4 11 11 C 1.53290 * 108.53608 * 231.08389 * 10 9 7 12 12 H 1.09001 * 109.51314 * 67.10409 * 11 10 9 13 13 C 1.53008 * 109.51017 * 187.19804 * 11 10 9 14 14 O 1.43107 * 109.23699 * 307.12281 * 11 10 9 15 15 C 1.42065 * 114.30295 * 61.17990 * 14 11 10 16 16 C 1.54518 * 110.33646 * 61.88929 * 15 14 11 17 17 C 1.55012 * 101.51764 * 83.94467 * 16 15 14 18 18 N 1.47487 * 104.90510 * 36.37416 * 17 16 15 19 19 C 1.36937 * 125.65514 * 155.96863 * 18 17 16 20 20 H 1.08002 * 119.99607 * 180.02562 * 19 18 17 21 21 C 1.38816 * 120.00475 * 0.02570 * 19 18 17 22 22 N 1.31614 * 119.99519 * 0.02562 * 21 19 18 23 23 Si 1.86798 * 120.00117 * 179.97438 * 21 19 18 24 24 H 1.48502 * 109.47027 * 60.00196 * 23 21 19 25 25 H 1.48501 * 109.47256 * 180.02562 * 23 21 19 26 26 H 1.48499 * 109.46853 * 300.00083 * 23 21 19 27 27 C 1.47184 * 108.68058 * 335.97343 * 18 17 16 28 28 C 1.47329 * 121.06005 * 174.30394 * 9 7 4 29 29 H 1.08998 * 109.47454 * 60.00493 * 1 2 3 30 30 H 1.09004 * 109.47107 * 179.97438 * 1 2 3 31 31 H 1.08996 * 109.47632 * 299.99645 * 1 2 3 32 32 H 1.08997 * 109.47434 * 59.99671 * 3 2 1 33 33 H 1.09006 * 109.47300 * 299.99881 * 3 2 1 34 34 H 1.09000 * 109.47213 * 195.21365 * 5 4 3 35 35 H 1.09008 * 109.47210 * 315.21220 * 5 4 3 36 36 H 1.08996 * 109.47264 * 75.20957 * 5 4 3 37 37 H 1.09000 * 109.47233 * 310.19155 * 6 4 3 38 38 H 1.09003 * 109.46886 * 70.18854 * 6 4 3 39 39 H 1.09000 * 109.47091 * 190.18757 * 6 4 3 40 40 H 1.09005 * 109.62501 * 111.37125 * 10 9 7 41 41 H 1.08997 * 109.62330 * 350.79847 * 10 9 7 42 42 H 1.08997 * 109.47132 * 59.99680 * 13 11 10 43 43 H 1.08994 * 109.46737 * 179.97438 * 13 11 10 44 44 H 1.08998 * 109.46449 * 300.00213 * 13 11 10 45 45 H 1.09004 * 111.01807 * 202.01445 * 16 15 14 46 46 H 1.09005 * 111.01229 * 325.85044 * 16 15 14 47 47 H 1.08997 * 110.35095 * 155.22803 * 17 16 15 48 48 H 1.08994 * 110.35711 * 277.41327 * 17 16 15 49 49 H 0.97002 * 119.99701 * 179.97438 * 22 21 19 50 50 H 1.09008 * 109.90465 * 242.15617 * 27 18 17 51 51 H 1.08993 * 109.91130 * 120.88526 * 27 18 17 52 52 H 1.09001 * 109.68428 * 10.88607 * 28 9 7 53 53 H 1.09005 * 109.68151 * 250.33055 * 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 1.4290 0.0000 0.0000 3 6 2.0101 1.3055 0.0000 4 6 3.5354 1.1848 -0.0006 5 6 3.9864 0.4258 -1.2501 6 6 3.9873 0.4254 1.2484 7 6 4.1482 2.5615 0.0000 8 8 3.4460 3.5379 0.1568 9 7 5.4767 2.7078 -0.1738 10 6 6.3670 1.5378 -0.2423 11 6 7.5217 1.7455 0.7442 12 1 7.1374 1.7245 1.7641 13 6 8.5544 0.6310 0.5643 14 8 8.1367 3.0125 0.4902 15 6 7.2701 4.1263 0.6535 16 6 6.7705 4.2085 2.1133 17 6 7.9388 4.9626 2.7984 18 7 8.4035 5.9361 1.7926 19 6 9.0700 7.1023 2.0589 20 1 9.3686 7.7508 1.2485 21 6 9.3620 7.4511 3.3705 22 7 8.9986 6.6606 4.3580 23 14 10.2719 9.0416 3.7335 24 1 9.4818 10.1912 3.2240 25 1 10.4598 9.1807 5.2000 26 1 11.5977 9.0170 3.0652 27 6 8.0318 5.4463 0.4554 28 6 6.0839 4.0440 -0.3015 29 1 -0.3634 0.5137 -0.8900 30 1 -0.3633 -1.0277 -0.0005 31 1 -0.3634 0.5137 0.8900 32 1 1.6884 1.8465 0.8899 33 1 1.6885 1.8464 -0.8900 34 1 5.0203 0.1036 -1.1261 35 1 3.3490 -0.4466 -1.3952 36 1 3.9112 1.0793 -2.1192 37 1 3.5165 0.8619 2.1292 38 1 3.6965 -0.6216 1.1621 39 1 5.0710 0.4948 1.3436 40 1 6.7626 1.4375 -1.2531 41 1 5.8121 0.6392 0.0274 42 1 8.9394 0.6536 -0.4552 43 1 9.3753 0.7797 1.2657 44 1 8.0842 -0.3339 0.7537 45 1 5.8446 4.7802 2.1781 46 1 6.6435 3.2133 2.5396 47 1 7.5852 5.4790 3.6908 48 1 8.7393 4.2688 3.0548 49 1 9.2030 6.9041 5.2745 50 1 8.9291 5.2716 -0.1385 51 1 7.3905 6.1741 -0.0415 52 1 5.3501 4.8072 -0.0422 53 1 6.4257 4.1956 -1.3255 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 ZINC001131673501.mol2 53 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 00:20:00 Heat of formation + Delta-G solvation = -73.389874 kcal Electronic energy + Delta-G solvation = -32696.505887 eV Core-core repulsion = 28570.361205 eV Total energy + Delta-G solvation = -4126.144682 eV No. of doubly occupied orbitals = 66 Molecular weight (most abundant/longest-lived isotopes) = 340.220 amu Computer time = 1.06 seconds Orbital eigenvalues (eV) -41.11582 -39.32304 -37.94644 -36.48878 -35.33368 -34.38846 -33.00341 -31.35229 -29.31872 -28.56584 -27.75068 -27.62894 -26.69488 -25.78990 -25.64514 -23.86504 -22.10988 -21.67391 -20.11725 -19.31296 -18.96772 -17.09806 -17.03374 -16.79587 -16.37849 -16.13478 -15.74758 -15.37397 -15.13141 -14.82373 -14.55082 -14.27295 -14.15378 -13.93510 -13.59592 -13.38764 -13.22811 -12.79039 -12.60163 -12.52435 -12.38694 -12.26230 -12.23861 -12.04788 -11.98132 -11.68976 -11.53825 -11.48524 -11.32250 -11.02596 -10.92457 -10.86299 -10.83433 -10.42964 -10.18707 -10.08082 -9.99738 -9.92380 -9.62194 -9.55888 -9.47043 -8.61609 -8.35827 -6.81108 -5.61773 -3.03544 2.53478 2.71173 3.43446 3.47012 3.48647 3.55224 3.82918 4.18608 4.50447 4.52765 4.56259 4.66112 4.81236 4.84976 5.03188 5.04845 5.06506 5.14223 5.16475 5.26927 5.30486 5.34422 5.36368 5.39525 5.47594 5.49868 5.52061 5.54750 5.57698 5.60561 5.71280 5.75098 5.84745 5.92970 5.93751 5.96599 6.02160 6.14567 6.24714 6.35131 6.54779 6.55736 6.61625 6.70062 6.84208 7.31087 7.55779 7.63086 7.66848 7.88404 8.06926 8.38033 9.24514 9.84967 10.50050 11.42210 Molecular weight = 340.22amu Principal moments of inertia in cm(-1) A = 0.018880 B = 0.002938 C = 0.002752 Principal moments of inertia in units of 10**(-40)*gram-cm**2 A = 1482.699859 B = 9528.468952 C =10171.458304 Net atomic charges, atomic populations, and dipole contributions calculated with CM2 Atom NO. Type Charge No. of electrons 1 C 0.033 3.967 2 O -0.389 6.389 3 C 0.087 3.913 4 C -0.078 4.078 5 C -0.152 4.152 6 C -0.147 4.147 7 C 0.529 3.471 8 O -0.539 6.539 9 N -0.604 5.604 10 C 0.058 3.942 11 C 0.066 3.934 12 H 0.067 0.933 13 C -0.142 4.142 14 O -0.352 6.352 15 C 0.096 3.904 16 C -0.164 4.164 17 C 0.161 3.839 18 N -0.601 5.601 19 C -0.221 4.221 20 H 0.078 0.922 21 C -0.011 4.011 22 N -0.922 5.922 23 Si 0.916 3.084 24 H -0.285 1.285 25 H -0.290 1.290 26 H -0.285 1.285 27 C 0.154 3.846 28 C 0.098 3.902 29 H 0.040 0.960 30 H 0.085 0.915 31 H 0.042 0.958 32 H 0.061 0.939 33 H 0.055 0.945 34 H 0.074 0.926 35 H 0.077 0.923 36 H 0.058 0.942 37 H 0.063 0.937 38 H 0.077 0.923 39 H 0.068 0.932 40 H 0.077 0.923 41 H 0.113 0.887 42 H 0.064 0.936 43 H 0.070 0.930 44 H 0.069 0.931 45 H 0.068 0.932 46 H 0.059 0.941 47 H 0.105 0.895 48 H 0.014 0.986 49 H 0.252 0.748 50 H 0.037 0.963 51 H 0.039 0.961 52 H 0.103 0.897 53 H 0.072 0.928 For the charges calculated by CM2: Dipole moment (debyes) X Y Z Total from point charges -12.040 -18.142 -10.378 24.121 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 -0.063 4.063 2 O -0.308 6.308 3 C 0.010 3.990 4 C -0.082 4.082 5 C -0.209 4.209 6 C -0.204 4.204 7 C 0.316 3.684 8 O -0.415 6.415 9 N -0.337 5.337 10 C -0.064 4.064 11 C 0.008 3.992 12 H 0.085 0.915 13 C -0.200 4.200 14 O -0.271 6.271 15 C 0.055 3.945 16 C -0.203 4.203 17 C 0.036 3.964 18 N -0.328 5.328 19 C -0.350 4.350 20 H 0.096 0.904 21 C -0.207 4.207 22 N -0.571 5.571 23 Si 0.746 3.254 24 H -0.211 1.211 25 H -0.216 1.216 26 H -0.212 1.212 27 C 0.028 3.972 28 C -0.025 4.025 29 H 0.059 0.941 30 H 0.104 0.896 31 H 0.060 0.940 32 H 0.079 0.921 33 H 0.073 0.927 34 H 0.092 0.908 35 H 0.096 0.904 36 H 0.077 0.923 37 H 0.082 0.918 38 H 0.096 0.904 39 H 0.087 0.913 40 H 0.095 0.905 41 H 0.130 0.870 42 H 0.083 0.917 43 H 0.089 0.911 44 H 0.088 0.912 45 H 0.086 0.914 46 H 0.078 0.922 47 H 0.123 0.877 48 H 0.032 0.968 49 H 0.063 0.937 50 H 0.054 0.946 51 H 0.057 0.943 52 H 0.121 0.879 53 H 0.090 0.910 Dipole moment (debyes) X Y Z Total from point charges -12.031 -17.624 -10.167 23.637 hybrid contribution 0.077 0.978 0.216 1.004 sum -11.955 -16.646 -9.951 22.782 Atomic orbital electron populations 1.22723 0.80831 1.02608 1.00181 1.87784 1.19699 1.27766 1.95515 1.22204 0.91033 0.84150 1.01647 1.20655 0.95100 0.93398 0.99001 1.22193 1.02500 1.00816 0.95392 1.22038 1.01674 1.01109 0.95589 1.20297 0.81713 0.90565 0.75778 1.90708 1.60596 1.41005 1.49220 1.48034 1.06066 1.07566 1.72027 1.23183 0.92518 0.89599 1.01128 1.22503 0.93024 0.85831 0.97864 0.91534 1.21709 0.99062 0.95851 1.03359 1.87915 1.36736 1.12587 1.89815 1.22276 0.89336 0.87857 0.94984 1.23495 1.01165 1.00498 0.95131 1.21870 0.90768 0.89873 0.93885 1.44488 1.67005 1.21866 0.99396 1.19024 1.28308 0.95380 0.92253 0.90434 1.24786 1.01440 0.98940 0.95499 1.69797 1.51598 1.37081 0.98622 0.86130 0.79499 0.82763 0.76966 1.21150 1.21609 1.21213 1.21057 0.96462 0.89341 0.90387 1.22223 0.95969 0.84419 0.99859 0.94099 0.89600 0.93968 0.92109 0.92678 0.90784 0.90395 0.92294 0.91761 0.90394 0.91327 0.90515 0.86982 0.91701 0.91088 0.91186 0.91356 0.92227 0.87724 0.96820 0.93716 0.94561 0.94341 0.87882 0.90996 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 0.03 0.24 11.01 101.05 1.11 1.35 16 2 O -0.39 -3.83 9.33 -35.23 -0.33 -4.15 16 3 C 0.09 0.94 4.12 37.16 0.15 1.10 16 4 C -0.08 -0.84 0.58 -155.66 -0.09 -0.93 16 5 C -0.15 -1.30 7.91 37.15 0.29 -1.01 16 6 C -0.15 -1.40 7.84 37.16 0.29 -1.11 16 7 C 0.53 7.45 6.43 -10.99 -0.07 7.38 16 8 O -0.54 -9.51 15.46 5.55 0.09 -9.42 16 9 N -0.60 -8.22 2.90 -172.58 -0.50 -8.72 16 10 C 0.06 0.63 3.52 -3.52 -0.01 0.62 16 11 C 0.07 0.87 3.14 -26.58 -0.08 0.78 16 12 H 0.07 0.93 6.13 -51.93 -0.32 0.61 16 13 C -0.14 -1.45 9.57 37.16 0.36 -1.09 16 14 O -0.35 -6.16 9.87 -35.23 -0.35 -6.51 16 15 C 0.10 1.77 0.83 -89.72 -0.07 1.69 16 16 C -0.16 -3.33 5.91 -24.87 -0.15 -3.47 16 17 C 0.16 4.06 5.89 -2.44 -0.01 4.05 16 18 N -0.60 -15.86 3.40 -170.23 -0.58 -16.44 16 19 C -0.22 -6.29 10.28 -15.06 -0.15 -6.45 16 20 H 0.08 2.11 7.83 -52.49 -0.41 1.70 16 21 C -0.01 -0.32 5.49 -17.43 -0.10 -0.42 16 22 N -0.92 -27.40 10.09 55.49 0.56 -26.84 16 23 Si 0.92 22.42 29.55 -169.99 -5.02 17.39 16 24 H -0.28 -6.86 7.11 56.52 0.40 -6.45 16 25 H -0.29 -7.14 7.11 56.52 0.40 -6.74 16 26 H -0.29 -6.89 7.11 56.52 0.40 -6.49 16 27 C 0.15 3.33 6.62 -3.32 -0.02 3.31 16 28 C 0.10 1.55 5.18 -3.84 -0.02 1.53 16 29 H 0.04 0.27 8.14 -51.93 -0.42 -0.15 16 30 H 0.09 0.47 8.14 -51.93 -0.42 0.05 16 31 H 0.04 0.29 8.14 -51.93 -0.42 -0.13 16 32 H 0.06 0.72 8.00 -51.93 -0.42 0.31 16 33 H 0.05 0.62 8.14 -51.93 -0.42 0.19 16 34 H 0.07 0.53 4.90 -51.93 -0.25 0.28 16 35 H 0.08 0.63 7.29 -51.92 -0.38 0.25 16 36 H 0.06 0.53 8.04 -51.93 -0.42 0.11 16 37 H 0.06 0.67 8.11 -51.93 -0.42 0.25 16 38 H 0.08 0.64 7.96 -51.93 -0.41 0.23 16 39 H 0.07 0.62 5.24 -51.93 -0.27 0.35 16 40 H 0.08 0.76 8.13 -51.93 -0.42 0.34 16 41 H 0.11 0.96 2.56 -51.93 -0.13 0.83 16 42 H 0.06 0.62 8.14 -51.93 -0.42 0.20 16 43 H 0.07 0.81 8.14 -51.93 -0.42 0.39 16 44 H 0.07 0.51 8.14 -51.93 -0.42 0.09 16 45 H 0.07 1.43 7.86 -51.93 -0.41 1.03 16 46 H 0.06 1.11 5.98 -51.93 -0.31 0.80 16 47 H 0.11 2.96 5.88 -51.93 -0.31 2.66 16 48 H 0.01 0.37 8.14 -51.93 -0.42 -0.05 16 49 H 0.25 7.27 8.31 -40.82 -0.34 6.93 16 50 H 0.04 0.80 8.06 -51.92 -0.42 0.38 16 51 H 0.04 0.80 7.79 -51.93 -0.40 0.40 16 52 H 0.10 1.80 6.87 -51.93 -0.36 1.44 16 53 H 0.07 1.04 8.14 -51.93 -0.42 0.62 16 LS Contribution 394.47 15.07 5.94 5.94 Total: -1.00 -33.24 394.47 -7.77 -41.01 By element: Atomic # 1 Polarization: 9.39 SS G_CDS: -9.00 Total: 0.39 kcal Atomic # 6 Polarization: 5.92 SS G_CDS: 1.42 Total: 7.34 kcal Atomic # 7 Polarization: -51.48 SS G_CDS: -0.52 Total: -51.99 kcal Atomic # 8 Polarization: -19.50 SS G_CDS: -0.59 Total: -20.09 kcal Atomic # 14 Polarization: 22.42 SS G_CDS: -5.02 Total: 17.39 kcal Total LS contribution 5.94 Total: 5.94 kcal Total: -33.24 -7.77 -41.01 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. ZINC001131673501.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 -32.383 kcal (2) G-P(sol) polarization free energy of solvation -33.238 kcal (3) G-ENP(sol) elect.-nuc.-pol. free energy of system -65.621 kcal (4) G-CDS(sol) cavity-dispersion-solvent structure free energy -7.769 kcal (5) G-P-CDS(sol) = G-P(sol) + G-CDS(sol) = (2) + (4) -41.007 kcal (6) G-S(sol) free energy of system = (1) + (5) -73.390 kcal 1SCF WAS SPECIFIED, SO GEOMETRY OPTIMIZATION WAS NOT USED Total computer time = 1.06 seconds