Wall clock time and date at job start Sat Apr 11 2020 06:11:46 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 1.52997 * 1 3 3 O 1.42905 * 109.47264 * 2 1 4 4 C 1.42893 * 114.00274 * 179.97438 * 3 2 1 5 5 H 1.09006 * 109.47387 * 329.99933 * 4 3 2 6 6 C 1.52996 * 109.47294 * 89.99893 * 4 3 2 7 7 C 1.50706 * 109.47501 * 210.00220 * 4 3 2 8 8 O 1.21274 * 119.99411 * 359.97438 * 7 4 3 9 9 N 1.34774 * 120.00012 * 180.02562 * 7 4 3 10 10 C 1.48188 * 127.80283 * 0.02562 * 9 7 4 11 11 C 1.54513 * 104.63592 * 219.26301 * 10 9 7 12 12 H 1.09001 * 110.37250 * 95.05190 * 11 10 9 13 13 C 1.53005 * 110.37583 * 217.39527 * 11 10 9 14 14 N 1.46498 * 109.47514 * 293.54671 * 13 11 10 15 15 C 1.36935 * 120.00020 * 180.02562 * 14 13 11 16 16 H 1.08000 * 120.00086 * 0.02562 * 15 14 13 17 17 C 1.38810 * 119.99683 * 180.02562 * 15 14 13 18 18 N 1.31618 * 120.00327 * 359.97438 * 17 15 14 19 19 Si 1.86798 * 119.99794 * 180.02562 * 17 15 14 20 20 H 1.48498 * 109.47517 * 59.99460 * 19 17 15 21 21 H 1.48507 * 109.47284 * 179.97438 * 19 17 15 22 22 H 1.48504 * 109.47010 * 299.99503 * 19 17 15 23 23 C 1.53771 * 104.78300 * 336.22494 * 11 10 9 24 24 C 1.48256 * 127.79619 * 179.70713 * 9 7 4 25 25 C 1.52592 * 110.28564 * 241.19438 * 23 11 10 26 26 C 1.53197 * 109.20125 * 182.29581 * 25 23 11 27 27 O 1.42908 * 109.34432 * 56.66998 * 26 25 23 28 28 C 1.42916 * 114.22054 * 298.39377 * 27 26 25 29 29 C 1.52594 * 110.26937 * 119.03399 * 23 11 10 30 30 H 1.09002 * 109.47153 * 179.97438 * 1 2 3 31 31 H 1.09001 * 109.46832 * 60.00108 * 1 2 3 32 32 H 1.09004 * 109.47261 * 300.00089 * 1 2 3 33 33 H 1.08998 * 109.47533 * 119.99712 * 2 1 3 34 34 H 1.08996 * 109.47853 * 240.00055 * 2 1 3 35 35 H 1.09003 * 109.47337 * 59.99910 * 6 4 3 36 36 H 1.09004 * 109.47410 * 180.02562 * 6 4 3 37 37 H 1.09005 * 109.47341 * 300.00407 * 6 4 3 38 38 H 1.09002 * 110.40513 * 338.06085 * 10 9 7 39 39 H 1.09009 * 110.40155 * 100.36286 * 10 9 7 40 40 H 1.08993 * 109.47112 * 53.55229 * 13 11 10 41 41 H 1.09004 * 109.46626 * 173.55103 * 13 11 10 42 42 H 0.97000 * 119.99500 * 0.02562 * 14 13 11 43 43 H 0.96999 * 120.00289 * 179.97438 * 18 17 15 44 44 H 1.09006 * 110.42666 * 259.63786 * 24 9 7 45 45 H 1.09000 * 110.43282 * 22.12179 * 24 9 7 46 46 H 1.08993 * 109.51439 * 302.21649 * 25 23 11 47 47 H 1.09003 * 109.51308 * 62.37654 * 25 23 11 48 48 H 1.09004 * 109.49253 * 296.70996 * 26 25 23 49 49 H 1.08998 * 109.51649 * 176.64554 * 26 25 23 50 50 H 1.09010 * 109.49505 * 301.65698 * 28 27 26 51 51 H 1.09002 * 109.51684 * 181.58990 * 28 27 26 52 52 H 1.09004 * 109.51408 * 297.63963 * 29 23 11 53 53 H 1.09003 * 109.51651 * 57.81104 * 29 23 11 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 2.0064 1.3473 0.0000 4 6 3.4308 1.4602 0.0006 5 1 3.8632 0.6017 0.5148 6 6 3.9399 1.5002 -1.4417 7 6 3.8342 2.7266 0.7110 8 8 2.9853 3.4604 1.1711 9 7 5.1382 3.0440 0.8342 10 6 6.3092 2.2814 0.3411 11 6 7.3631 2.4157 1.4630 12 1 7.3167 1.5565 2.1321 13 6 8.7646 2.5509 0.8641 14 7 9.1308 1.3021 0.1914 15 6 10.3494 1.1869 -0.4224 16 1 11.0408 2.0165 -0.4103 17 6 10.6962 0.0037 -1.0602 18 7 9.8538 -1.0075 -1.0746 19 14 12.3588 -0.1537 -1.8969 20 1 13.4376 0.0436 -0.8956 21 1 12.4841 -1.5055 -2.4989 22 1 12.4769 0.8754 -2.9610 23 6 6.9755 3.7005 2.2138 24 6 5.7248 4.2384 1.4879 25 6 8.1063 4.7218 2.1335 26 6 7.7181 5.9676 2.9362 27 8 7.4208 5.5898 4.2820 28 6 6.3211 4.6857 4.4079 29 6 6.6482 3.3835 3.6701 30 1 -0.3633 -1.0277 -0.0005 31 1 -0.3633 0.5138 -0.8900 32 1 -0.3634 0.5139 0.8900 33 1 1.8934 -0.5138 0.8900 34 1 1.8934 -0.5138 -0.8899 35 1 3.5076 2.3586 -1.9559 36 1 5.0265 1.5859 -1.4412 37 1 3.6481 0.5842 -1.9555 38 1 6.0452 1.2346 0.1910 39 1 6.6820 2.7153 -0.5868 40 1 8.7743 3.3683 0.1431 41 1 9.4808 2.7590 1.6590 42 1 8.5100 0.5568 0.1808 43 1 10.0960 -1.8342 -1.5206 44 1 6.0054 4.9815 0.7413 45 1 5.0218 4.6641 2.2040 46 1 9.0169 4.2902 2.5487 47 1 8.2748 4.9973 1.0924 48 1 6.8402 6.4313 2.4862 49 1 8.5462 6.6763 2.9318 50 1 5.4285 5.1357 3.9732 51 1 6.1442 4.4720 5.4620 52 1 5.7883 2.7149 3.7128 53 1 7.5069 2.9043 4.1403 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 ZINC001186273812.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 06:11:46 Heat of formation + Delta-G solvation = -112.689829 kcal Electronic energy + Delta-G solvation = -32010.365467 eV Core-core repulsion = 27882.516610 eV Total energy + Delta-G solvation = -4127.848856 eV No. of doubly occupied orbitals = 66 Molecular weight (most abundant/longest-lived isotopes) = 340.220 amu Computer time = 1.01 seconds Orbital eigenvalues (eV) -41.03506 -39.48715 -37.88830 -37.15380 -34.70670 -33.70015 -32.34422 -31.74059 -31.15999 -30.25754 -29.27043 -27.03274 -25.77343 -24.76031 -23.80903 -23.71255 -22.74840 -22.31932 -20.65279 -19.52609 -18.53696 -17.47417 -17.07975 -16.78239 -16.11089 -16.01283 -15.86038 -15.65925 -15.59508 -14.90471 -14.64822 -14.51472 -14.37334 -13.98594 -13.48371 -13.39671 -13.27888 -13.12965 -12.78993 -12.64692 -12.56596 -12.34919 -12.25346 -12.14722 -12.02556 -11.81918 -11.57073 -11.45950 -11.30074 -11.22375 -11.10309 -10.98518 -10.85437 -10.69950 -10.26768 -10.11298 -10.07041 -9.96610 -9.76660 -9.49739 -9.39159 -8.93501 -8.69733 -7.00903 -5.84673 -3.13523 2.57757 2.67030 3.39086 3.44306 3.44515 3.70008 3.83684 4.29120 4.45205 4.56380 4.58286 4.63398 4.78881 4.82229 4.96790 4.97077 5.03194 5.06771 5.09646 5.15241 5.18372 5.28046 5.34125 5.36529 5.44539 5.49982 5.52650 5.60377 5.61645 5.62126 5.66044 5.68978 5.72777 5.80155 5.86723 5.91640 5.94076 5.99564 6.02857 6.06720 6.12409 6.23293 6.28236 6.36483 6.65689 6.73848 6.96891 7.15036 7.53272 7.62714 8.16563 8.34025 9.45696 10.01383 10.35809 11.37975 Molecular weight = 340.22amu Principal moments of inertia in cm(-1) A = 0.007274 B = 0.004158 C = 0.002796 Principal moments of inertia in units of 10**(-40)*gram-cm**2 A = 3848.606017 B = 6731.663651 C =10011.049899 Net atomic charges, atomic populations, and dipole contributions calculated with CM2 Atom NO. Type Charge No. of electrons 1 C -0.149 4.149 2 C 0.054 3.946 3 O -0.360 6.360 4 C 0.076 3.924 5 H 0.087 0.913 6 C -0.177 4.177 7 C 0.538 3.462 8 O -0.530 6.530 9 N -0.620 5.620 10 C 0.106 3.894 11 C -0.097 4.097 12 H 0.084 0.916 13 C 0.162 3.838 14 N -0.733 5.733 15 C -0.241 4.241 16 H 0.070 0.930 17 C -0.011 4.011 18 N -0.933 5.933 19 Si 0.906 3.094 20 H -0.286 1.286 21 H -0.291 1.291 22 H -0.286 1.286 23 C -0.064 4.064 24 C 0.114 3.886 25 C -0.145 4.145 26 C 0.058 3.942 27 O -0.383 6.383 28 C 0.060 3.940 29 C -0.139 4.139 30 H 0.071 0.929 31 H 0.063 0.937 32 H 0.063 0.937 33 H 0.050 0.950 34 H 0.052 0.948 35 H 0.067 0.933 36 H 0.083 0.917 37 H 0.070 0.930 38 H 0.082 0.918 39 H 0.083 0.917 40 H 0.024 0.976 41 H 0.028 0.972 42 H 0.382 0.618 43 H 0.256 0.744 44 H 0.073 0.927 45 H 0.082 0.918 46 H 0.086 0.914 47 H 0.083 0.917 48 H 0.048 0.952 49 H 0.094 0.906 50 H 0.050 0.950 51 H 0.092 0.908 52 H 0.072 0.928 53 H 0.078 0.922 For the charges calculated by CM2: Dipole moment (debyes) X Y Z Total from point charges -12.769 6.986 5.382 15.518 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 -0.207 4.207 2 C -0.023 4.023 3 O -0.279 6.279 4 C 0.015 3.985 5 H 0.105 0.895 6 C -0.234 4.234 7 C 0.326 3.674 8 O -0.405 6.405 9 N -0.355 5.355 10 C -0.016 4.016 11 C -0.117 4.117 12 H 0.103 0.897 13 C 0.035 3.965 14 N -0.377 5.377 15 C -0.372 4.372 16 H 0.088 0.912 17 C -0.207 4.207 18 N -0.582 5.582 19 Si 0.737 3.263 20 H -0.213 1.213 21 H -0.217 1.217 22 H -0.213 1.213 23 C -0.066 4.066 24 C -0.008 4.008 25 C -0.183 4.183 26 C -0.018 4.018 27 O -0.302 6.302 28 C -0.017 4.017 29 C -0.176 4.176 30 H 0.090 0.910 31 H 0.082 0.918 32 H 0.082 0.918 33 H 0.068 0.932 34 H 0.070 0.930 35 H 0.086 0.914 36 H 0.102 0.898 37 H 0.089 0.911 38 H 0.101 0.899 39 H 0.102 0.898 40 H 0.042 0.958 41 H 0.045 0.955 42 H 0.216 0.784 43 H 0.066 0.934 44 H 0.091 0.909 45 H 0.100 0.900 46 H 0.105 0.895 47 H 0.101 0.899 48 H 0.066 0.934 49 H 0.112 0.888 50 H 0.068 0.932 51 H 0.110 0.890 52 H 0.090 0.910 53 H 0.097 0.903 Dipole moment (debyes) X Y Z Total from point charges -13.234 7.595 5.698 16.288 hybrid contribution 0.851 -0.953 -0.850 1.535 sum -12.383 6.642 4.848 14.864 Atomic orbital electron populations 1.21720 0.93504 1.02157 1.03273 1.22595 0.95819 0.83549 1.00325 1.88011 1.18487 1.26375 1.94994 1.21783 0.83415 0.96297 0.96995 0.89489 1.22368 1.02871 1.03592 0.94608 1.19967 0.80599 0.87174 0.79679 1.90693 1.49203 1.52018 1.48634 1.48974 1.04686 1.24625 1.57253 1.22710 0.84221 0.96997 0.97704 1.22312 0.96105 0.96966 0.96316 0.89750 1.20840 0.90723 0.90453 0.94525 1.42367 1.18490 1.11909 1.64946 1.19151 0.93105 0.98188 1.26757 0.91230 1.24710 0.98288 0.96266 1.01431 1.69629 1.35698 1.04183 1.48671 0.86291 0.83871 0.76769 0.79378 1.21264 1.21692 1.21254 1.21139 0.94571 0.95842 0.95006 1.22549 0.93988 0.87831 0.96441 1.22308 0.98803 0.95462 1.01701 1.22682 1.00286 0.96184 0.82693 1.87908 1.51499 1.64215 1.26587 1.22648 0.88917 0.89296 1.00855 1.22142 1.02734 0.98227 0.94527 0.91038 0.91813 0.91762 0.93203 0.93012 0.91350 0.89845 0.91129 0.89936 0.89837 0.95796 0.95477 0.78429 0.93445 0.90894 0.90016 0.89514 0.89868 0.93406 0.88832 0.93156 0.89011 0.90959 0.90339 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 -1.31 10.28 37.16 0.38 -0.93 16 2 C 0.05 0.56 6.47 37.16 0.24 0.80 16 3 O -0.36 -5.03 9.52 -55.14 -0.52 -5.55 16 4 C 0.08 1.00 2.47 -27.88 -0.07 0.93 16 5 H 0.09 1.01 7.60 -51.93 -0.39 0.62 16 6 C -0.18 -2.08 9.28 37.16 0.34 -1.73 16 7 C 0.54 8.20 7.34 -10.98 -0.08 8.12 16 8 O -0.53 -9.91 16.77 -14.35 -0.24 -10.15 16 9 N -0.62 -8.40 3.31 -169.16 -0.56 -8.96 16 10 C 0.11 1.44 4.47 -2.32 -0.01 1.43 16 11 C -0.10 -1.37 2.78 -89.42 -0.25 -1.62 16 12 H 0.08 1.26 7.70 -51.93 -0.40 0.86 16 13 C 0.16 2.83 4.39 -4.04 -0.02 2.82 16 14 N -0.73 -16.75 5.44 -59.91 -0.33 -17.08 16 15 C -0.24 -6.31 9.99 -15.06 -0.15 -6.46 16 16 H 0.07 1.78 7.83 -52.49 -0.41 1.37 16 17 C -0.01 -0.30 5.50 -17.43 -0.10 -0.39 16 18 N -0.93 -26.66 13.06 55.49 0.72 -25.94 16 19 Si 0.91 21.51 29.55 -169.99 -5.02 16.49 16 20 H -0.29 -6.73 7.11 56.52 0.40 -6.33 16 21 H -0.29 -7.00 7.11 56.52 0.40 -6.60 16 22 H -0.29 -6.69 7.11 56.52 0.40 -6.29 16 23 C -0.06 -0.77 0.69 -153.85 -0.11 -0.87 16 24 C 0.11 1.42 5.12 -2.40 -0.01 1.41 16 25 C -0.14 -1.65 3.63 -26.84 -0.10 -1.75 16 26 C 0.06 0.61 6.65 37.26 0.25 0.86 16 27 O -0.38 -4.70 10.75 -35.23 -0.38 -5.07 16 28 C 0.06 0.65 6.64 37.26 0.25 0.89 16 29 C -0.14 -1.60 4.68 -26.83 -0.13 -1.72 16 30 H 0.07 0.47 8.14 -51.93 -0.42 0.05 16 31 H 0.06 0.56 8.14 -51.93 -0.42 0.14 16 32 H 0.06 0.60 8.14 -51.93 -0.42 0.18 16 33 H 0.05 0.48 8.08 -51.93 -0.42 0.06 16 34 H 0.05 0.47 7.87 -51.93 -0.41 0.06 16 35 H 0.07 0.83 8.14 -51.93 -0.42 0.41 16 36 H 0.08 0.99 5.33 -51.93 -0.28 0.72 16 37 H 0.07 0.74 7.87 -51.93 -0.41 0.33 16 38 H 0.08 1.11 6.58 -51.93 -0.34 0.77 16 39 H 0.08 1.20 7.66 -51.92 -0.40 0.80 16 40 H 0.02 0.42 6.88 -51.93 -0.36 0.06 16 41 H 0.03 0.50 6.62 -51.93 -0.34 0.15 16 42 H 0.38 9.14 7.52 -40.82 -0.31 8.84 16 43 H 0.26 7.15 8.31 -40.82 -0.34 6.81 16 44 H 0.07 0.85 7.78 -51.93 -0.40 0.45 16 45 H 0.08 1.06 5.95 -51.93 -0.31 0.75 16 46 H 0.09 1.09 6.60 -51.93 -0.34 0.75 16 47 H 0.08 0.92 6.87 -51.93 -0.36 0.56 16 48 H 0.05 0.46 7.54 -51.93 -0.39 0.07 16 49 H 0.09 0.86 8.14 -51.93 -0.42 0.43 16 50 H 0.05 0.54 6.53 -51.92 -0.34 0.20 16 51 H 0.09 0.88 8.14 -51.93 -0.42 0.46 16 52 H 0.07 0.85 8.14 -51.93 -0.42 0.43 16 53 H 0.08 0.94 8.14 -51.93 -0.42 0.52 16 LS Contribution 402.36 15.07 6.06 6.06 Total: -1.00 -31.85 402.36 -8.94 -40.80 By element: Atomic # 1 Polarization: 16.75 SS G_CDS: -9.13 Total: 7.62 kcal Atomic # 6 Polarization: 1.32 SS G_CDS: 0.45 Total: 1.77 kcal Atomic # 7 Polarization: -51.81 SS G_CDS: -0.16 Total: -51.97 kcal Atomic # 8 Polarization: -19.63 SS G_CDS: -1.14 Total: -20.77 kcal Atomic # 14 Polarization: 21.51 SS G_CDS: -5.02 Total: 16.49 kcal Total LS contribution 6.06 Total: 6.06 kcal Total: -31.85 -8.94 -40.80 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. ZINC001186273812.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 -71.894 kcal (2) G-P(sol) polarization free energy of solvation -31.853 kcal (3) G-ENP(sol) elect.-nuc.-pol. free energy of system -103.747 kcal (4) G-CDS(sol) cavity-dispersion-solvent structure free energy -8.942 kcal (5) G-P-CDS(sol) = G-P(sol) + G-CDS(sol) = (2) + (4) -40.796 kcal (6) G-S(sol) free energy of system = (1) + (5) -112.690 kcal 1SCF WAS SPECIFIED, SO GEOMETRY OPTIMIZATION WAS NOT USED Total computer time = 1.01 seconds