Wall clock time and date at job start Sat Apr 11 2020 06:11:51 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 1.42904 * 1 3 3 C 1.42902 * 113.99688 * 2 1 4 4 C 1.52998 * 109.47203 * 179.97438 * 3 2 1 5 5 C 1.50697 * 109.47170 * 305.20543 * 4 3 2 6 6 O 1.21280 * 120.00152 * 127.42694 * 5 4 3 7 7 N 1.34774 * 119.99783 * 307.42878 * 5 4 3 8 8 C 1.47149 * 120.98302 * 355.49788 * 7 5 4 9 9 C 1.53300 * 108.38569 * 230.51388 * 8 7 5 10 10 O 1.42961 * 109.21926 * 307.69911 * 9 8 7 11 11 C 1.42960 * 114.17081 * 62.58344 * 10 9 8 12 12 H 1.09002 * 109.51486 * 57.33674 * 11 10 9 13 13 C 1.52996 * 109.51792 * 177.49040 * 11 10 9 14 14 N 1.46498 * 109.46952 * 299.74603 * 13 11 10 15 15 C 1.36936 * 119.99821 * 179.97438 * 14 13 11 16 16 H 1.07994 * 120.00253 * 0.02562 * 15 14 13 17 17 C 1.38813 * 119.99932 * 180.02562 * 15 14 13 18 18 N 1.31624 * 120.00256 * 0.02562 * 17 15 14 19 19 Si 1.86803 * 120.00195 * 180.02562 * 17 15 14 20 20 H 1.48499 * 109.47098 * 89.99435 * 19 17 15 21 21 H 1.48497 * 109.47417 * 210.00025 * 19 17 15 22 22 H 1.48498 * 109.46948 * 329.99963 * 19 17 15 23 23 C 1.47156 * 120.98281 * 175.47920 * 7 5 4 24 24 C 1.53005 * 109.46852 * 65.20573 * 4 3 2 25 25 C 1.52998 * 109.46852 * 179.97438 * 24 4 3 26 26 C 1.53001 * 109.47510 * 299.99836 * 25 24 4 27 27 C 1.52995 * 109.46847 * 59.99821 * 26 25 24 28 28 C 1.53003 * 109.47014 * 185.20229 * 4 3 2 29 29 H 1.08995 * 109.47100 * 300.00016 * 1 2 3 30 30 H 1.09000 * 109.47224 * 60.00572 * 1 2 3 31 31 H 1.09002 * 109.46408 * 179.97438 * 1 2 3 32 32 H 1.09002 * 109.47338 * 59.99813 * 3 2 1 33 33 H 1.09001 * 109.47000 * 299.99589 * 3 2 1 34 34 H 1.08999 * 109.68127 * 350.23802 * 8 7 5 35 35 H 1.09004 * 109.68030 * 110.75689 * 8 7 5 36 36 H 1.08993 * 109.50906 * 67.62244 * 9 8 7 37 37 H 1.08999 * 109.50892 * 187.77455 * 9 8 7 38 38 H 1.08998 * 109.46717 * 59.74176 * 13 11 10 39 39 H 1.08999 * 109.47497 * 179.74700 * 13 11 10 40 40 H 0.96997 * 120.00444 * 359.97438 * 14 13 11 41 41 H 0.96993 * 119.99911 * 180.02562 * 18 17 15 42 42 H 1.09004 * 109.67800 * 249.21356 * 23 7 5 43 43 H 1.09009 * 109.67823 * 9.75879 * 23 7 5 44 44 H 1.08997 * 109.47143 * 299.99529 * 24 4 3 45 45 H 1.08995 * 109.47290 * 59.99690 * 24 4 3 46 46 H 1.09001 * 109.47176 * 179.97438 * 25 24 4 47 47 H 1.09005 * 109.47220 * 60.00306 * 25 24 4 48 48 H 1.09005 * 109.46748 * 300.00334 * 26 25 24 49 49 H 1.08999 * 109.47531 * 180.02562 * 26 25 24 50 50 H 1.09006 * 109.47244 * 180.02562 * 27 26 25 51 51 H 1.09004 * 109.47422 * 60.00317 * 27 26 25 52 52 H 1.08994 * 109.47221 * 299.99758 * 28 4 3 53 53 H 1.08995 * 109.47316 * 60.00349 * 28 4 3 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 2.0102 1.3055 0.0000 4 6 3.5354 1.1848 0.0006 5 6 3.9711 0.3288 1.1619 6 8 4.7025 -0.6203 0.9748 7 7 3.5479 0.6181 2.4083 8 6 2.7411 1.8196 2.6746 9 6 3.3798 2.5820 3.8412 10 8 3.5690 1.6878 4.9405 11 6 4.4617 0.6051 4.6674 12 1 5.4294 1.0002 4.3582 13 6 4.6348 -0.2451 5.9275 14 7 5.1921 0.5811 7.0012 15 6 5.4349 0.0319 8.2319 16 1 5.2158 -1.0103 8.4109 17 6 5.9625 0.8149 9.2495 18 7 6.2290 2.0853 9.0316 19 14 6.2943 0.0656 10.9282 20 1 7.6770 -0.4747 10.9645 21 1 6.1427 1.1084 11.9745 22 1 5.3270 -1.0326 11.1800 23 6 3.8785 -0.2585 3.5431 24 6 3.9966 0.5413 -1.3086 25 6 5.5218 0.4212 -1.3083 26 6 6.1431 1.8132 -1.1777 27 6 5.6819 2.4568 0.1314 28 6 4.1571 2.5767 0.1314 29 1 -0.3633 0.5138 0.8899 30 1 -0.3633 0.5137 -0.8900 31 1 -0.3632 -1.0277 -0.0005 32 1 1.6885 1.8465 0.8900 33 1 1.6886 1.8464 -0.8900 34 1 2.7228 2.4534 1.7881 35 1 1.7245 1.5280 2.9386 36 1 4.3434 2.9843 3.5291 37 1 2.7245 3.3985 4.1447 38 1 3.6661 -0.6376 6.2367 39 1 5.3120 -1.0729 5.7172 40 1 5.3892 1.5171 6.8405 41 1 6.5981 2.6323 9.7426 42 1 2.9766 -0.7593 3.8950 43 1 4.6134 -1.0009 3.2315 44 1 3.5537 -0.4503 -1.4018 45 1 3.6814 1.1603 -2.1485 46 1 5.8504 -0.0377 -2.2408 47 1 5.8374 -0.1978 -0.4683 48 1 5.8275 2.4321 -2.0177 49 1 7.2298 1.7277 -1.1779 50 1 6.1241 3.4487 0.2243 51 1 5.9974 1.8379 0.9715 52 1 3.8420 3.1958 -0.7085 53 1 3.8286 3.0352 1.0641 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 ZINC001570142321.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 06:11:51 Heat of formation + Delta-G solvation = -96.977151 kcal Electronic energy + Delta-G solvation = -32575.542680 eV Core-core repulsion = 28448.375176 eV Total energy + Delta-G solvation = -4127.167503 eV No. of doubly occupied orbitals = 66 Molecular weight (most abundant/longest-lived isotopes) = 340.220 amu Computer time = 0.68 seconds Orbital eigenvalues (eV) -41.47828 -39.00312 -37.91590 -37.01786 -35.22407 -34.38912 -32.70893 -31.92265 -30.94904 -30.08094 -28.15702 -27.44492 -25.88195 -25.34319 -23.71340 -23.19323 -22.77965 -21.69314 -20.92614 -20.48527 -18.96294 -17.16018 -17.01940 -16.72215 -16.43341 -16.02264 -15.91102 -15.79998 -15.35616 -15.12794 -14.66700 -14.45773 -14.20432 -14.09149 -14.01381 -13.77526 -13.31996 -13.14565 -12.99194 -12.76119 -12.56581 -12.36579 -12.26249 -12.08889 -12.08157 -11.84423 -11.61091 -11.54835 -11.19977 -10.98705 -10.89082 -10.86278 -10.76768 -10.42672 -10.33435 -10.25649 -10.02858 -9.92008 -9.73725 -9.65576 -9.34132 -8.83645 -8.42770 -6.85846 -5.70106 -2.98510 2.62319 2.83275 3.34028 3.47827 3.52575 3.54520 3.94624 4.07982 4.38504 4.44656 4.60028 4.64633 4.68623 4.71730 4.83494 4.88805 5.00339 5.01299 5.05649 5.09079 5.10677 5.17882 5.19631 5.27780 5.29445 5.32405 5.37944 5.40377 5.48749 5.61761 5.62751 5.67192 5.70710 5.71805 5.81808 5.91625 5.96542 5.99395 6.02259 6.10254 6.18871 6.30854 6.37934 6.53982 6.59745 6.73381 6.77994 7.36675 7.48854 7.74777 8.18549 8.48169 9.59893 10.17413 10.53623 11.52744 Molecular weight = 340.22amu Principal moments of inertia in cm(-1) A = 0.017020 B = 0.002806 C = 0.002651 Principal moments of inertia in units of 10**(-40)*gram-cm**2 A = 1644.709523 B = 9976.773572 C =10558.997701 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 -0.381 6.381 3 C 0.053 3.947 4 C -0.073 4.073 5 C 0.543 3.457 6 O -0.530 6.530 7 N -0.608 5.608 8 C 0.053 3.947 9 C 0.045 3.955 10 O -0.356 6.356 11 C 0.075 3.925 12 H 0.062 0.938 13 C 0.163 3.837 14 N -0.726 5.726 15 C -0.238 4.238 16 H 0.070 0.930 17 C -0.014 4.014 18 N -0.932 5.932 19 Si 0.907 3.093 20 H -0.290 1.290 21 H -0.292 1.292 22 H -0.282 1.282 23 C 0.087 3.913 24 C -0.085 4.085 25 C -0.140 4.140 26 C -0.117 4.117 27 C -0.121 4.121 28 C -0.118 4.118 29 H 0.042 0.958 30 H 0.040 0.960 31 H 0.086 0.914 32 H 0.068 0.932 33 H 0.058 0.942 34 H 0.106 0.894 35 H 0.075 0.925 36 H 0.054 0.946 37 H 0.103 0.897 38 H 0.028 0.972 39 H 0.035 0.965 40 H 0.388 0.612 41 H 0.254 0.746 42 H 0.075 0.925 43 H 0.101 0.899 44 H 0.073 0.927 45 H 0.062 0.938 46 H 0.057 0.943 47 H 0.100 0.900 48 H 0.057 0.943 49 H 0.061 0.939 50 H 0.068 0.932 51 H 0.065 0.935 52 H 0.078 0.922 53 H 0.078 0.922 For the charges calculated by CM2: Dipole moment (debyes) X Y Z Total from point charges -10.221 2.975 -25.380 27.522 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 -0.064 4.064 2 O -0.300 6.300 3 C -0.023 4.023 4 C -0.077 4.077 5 C 0.331 3.669 6 O -0.406 6.406 7 N -0.342 5.342 8 C -0.069 4.069 9 C -0.034 4.034 10 O -0.274 6.274 11 C 0.016 3.984 12 H 0.080 0.920 13 C 0.035 3.965 14 N -0.370 5.370 15 C -0.370 4.370 16 H 0.088 0.912 17 C -0.210 4.210 18 N -0.581 5.581 19 Si 0.739 3.261 20 H -0.218 1.218 21 H -0.218 1.218 22 H -0.208 1.208 23 C -0.036 4.036 24 C -0.123 4.123 25 C -0.177 4.177 26 C -0.155 4.155 27 C -0.159 4.159 28 C -0.155 4.155 29 H 0.060 0.940 30 H 0.059 0.941 31 H 0.105 0.895 32 H 0.086 0.914 33 H 0.076 0.924 34 H 0.124 0.876 35 H 0.093 0.907 36 H 0.072 0.928 37 H 0.121 0.879 38 H 0.046 0.954 39 H 0.053 0.947 40 H 0.222 0.778 41 H 0.064 0.936 42 H 0.094 0.906 43 H 0.119 0.881 44 H 0.092 0.908 45 H 0.081 0.919 46 H 0.075 0.925 47 H 0.119 0.881 48 H 0.076 0.924 49 H 0.080 0.920 50 H 0.087 0.913 51 H 0.083 0.917 52 H 0.096 0.904 53 H 0.096 0.904 Dipole moment (debyes) X Y Z Total from point charges -9.804 2.190 -25.162 27.093 hybrid contribution -0.054 0.285 0.649 0.711 sum -9.859 2.475 -24.513 26.537 Atomic orbital electron populations 1.22747 0.80825 1.02977 0.99892 1.87958 1.19722 1.26929 1.95349 1.23039 0.91822 0.85900 1.01566 1.20872 0.94126 0.96710 0.95949 1.20106 0.79226 0.84674 0.82901 1.90568 1.36231 1.30185 1.83636 1.48012 1.53374 1.25327 1.07448 1.23096 0.95706 0.87774 1.00372 1.22942 1.00367 0.92712 0.87336 1.88163 1.65827 1.38281 1.35094 1.22789 0.92122 0.87869 0.95633 0.92005 1.20623 0.97041 0.92559 0.86259 1.42209 1.76055 1.10506 1.08244 1.19234 1.34825 0.94683 0.88213 0.91164 1.24737 1.02165 0.95804 0.98295 1.69677 1.50186 1.05536 1.32679 0.86181 0.77983 0.77827 0.84152 1.21766 1.21812 1.20765 1.22305 1.01982 0.93579 0.85723 1.21287 0.96702 1.01001 0.93326 1.21921 0.94574 0.97458 1.03751 1.21525 1.00236 0.96780 0.96911 1.21526 0.94225 1.01253 0.98862 1.21840 0.96762 0.93775 1.03100 0.93958 0.94099 0.89524 0.91409 0.92363 0.87634 0.90687 0.92817 0.87911 0.95417 0.94707 0.77847 0.93603 0.90636 0.88089 0.90793 0.91937 0.92462 0.88146 0.92426 0.92023 0.91324 0.91669 0.90374 0.90404 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 -0.38 -4.03 9.72 -35.23 -0.34 -4.37 16 3 C 0.05 0.45 4.38 37.16 0.16 0.61 16 4 C -0.07 -0.73 0.34 -155.66 -0.05 -0.78 16 5 C 0.54 7.30 4.59 -10.99 -0.05 7.25 16 6 O -0.53 -8.80 12.89 5.56 0.07 -8.73 16 7 N -0.61 -7.97 3.01 -172.27 -0.52 -8.48 16 8 C 0.05 0.55 4.29 -3.53 -0.02 0.54 16 9 C 0.04 0.55 6.99 37.31 0.26 0.81 16 10 O -0.36 -6.27 10.14 -35.23 -0.36 -6.63 16 11 C 0.07 1.31 2.86 -26.58 -0.08 1.23 16 12 H 0.06 1.14 8.14 -51.93 -0.42 0.71 16 13 C 0.16 3.44 5.95 -4.04 -0.02 3.41 16 14 N -0.73 -19.21 5.50 -59.91 -0.33 -19.53 16 15 C -0.24 -6.88 9.99 -15.06 -0.15 -7.03 16 16 H 0.07 1.95 7.83 -52.49 -0.41 1.54 16 17 C -0.01 -0.42 5.50 -17.43 -0.10 -0.51 16 18 N -0.93 -28.84 13.06 55.49 0.72 -28.12 16 19 Si 0.91 22.86 29.55 -169.99 -5.02 17.83 16 20 H -0.29 -7.26 7.11 56.52 0.40 -6.86 16 21 H -0.29 -7.38 7.11 56.52 0.40 -6.97 16 22 H -0.28 -6.90 7.11 56.52 0.40 -6.50 16 23 C 0.09 1.31 5.94 -3.53 -0.02 1.29 16 24 C -0.09 -0.87 4.32 -26.73 -0.12 -0.98 16 25 C -0.14 -1.50 5.63 -26.73 -0.15 -1.65 16 26 C -0.12 -1.07 5.92 -26.73 -0.16 -1.23 16 27 C -0.12 -1.15 5.70 -26.76 -0.15 -1.30 16 28 C -0.12 -0.95 4.47 -26.75 -0.12 -1.07 16 29 H 0.04 0.28 8.14 -51.93 -0.42 -0.15 16 30 H 0.04 0.23 8.14 -51.93 -0.42 -0.19 16 31 H 0.09 0.59 8.14 -51.93 -0.42 0.16 16 32 H 0.07 0.50 4.46 -51.93 -0.23 0.27 16 33 H 0.06 0.38 8.14 -51.93 -0.42 -0.04 16 34 H 0.11 0.82 2.51 -51.93 -0.13 0.69 16 35 H 0.07 0.75 8.02 -51.93 -0.42 0.34 16 36 H 0.05 0.66 8.14 -51.93 -0.42 0.23 16 37 H 0.10 1.05 8.14 -51.93 -0.42 0.63 16 38 H 0.03 0.59 8.14 -51.93 -0.42 0.17 16 39 H 0.04 0.72 8.14 -51.93 -0.42 0.30 16 40 H 0.39 10.88 7.55 -40.82 -0.31 10.57 16 41 H 0.25 7.57 8.31 -40.82 -0.34 7.23 16 42 H 0.08 1.11 8.14 -51.93 -0.42 0.69 16 43 H 0.10 1.60 7.07 -51.92 -0.37 1.23 16 44 H 0.07 0.88 7.83 -51.93 -0.41 0.48 16 45 H 0.06 0.51 8.14 -51.93 -0.42 0.09 16 46 H 0.06 0.56 8.14 -51.93 -0.42 0.14 16 47 H 0.10 1.39 5.25 -51.93 -0.27 1.12 16 48 H 0.06 0.45 8.14 -51.93 -0.42 0.02 16 49 H 0.06 0.56 8.14 -51.93 -0.42 0.14 16 50 H 0.07 0.56 8.14 -51.93 -0.42 0.14 16 51 H 0.06 0.79 7.22 -51.93 -0.37 0.41 16 52 H 0.08 0.48 8.14 -51.93 -0.42 0.06 16 53 H 0.08 0.58 5.08 -51.93 -0.26 0.31 16 LS Contribution 394.47 15.07 5.94 5.94 Total: -1.00 -34.62 394.47 -8.56 -43.18 By element: Atomic # 1 Polarization: 16.05 SS G_CDS: -9.08 Total: 6.97 kcal Atomic # 6 Polarization: 1.59 SS G_CDS: 0.35 Total: 1.94 kcal Atomic # 7 Polarization: -56.01 SS G_CDS: -0.12 Total: -56.14 kcal Atomic # 8 Polarization: -19.10 SS G_CDS: -0.63 Total: -19.73 kcal Atomic # 14 Polarization: 22.86 SS G_CDS: -5.02 Total: 17.83 kcal Total LS contribution 5.94 Total: 5.94 kcal Total: -34.62 -8.56 -43.18 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. ZINC001570142321.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 -53.795 kcal (2) G-P(sol) polarization free energy of solvation -34.623 kcal (3) G-ENP(sol) elect.-nuc.-pol. free energy of system -88.418 kcal (4) G-CDS(sol) cavity-dispersion-solvent structure free energy -8.559 kcal (5) G-P-CDS(sol) = G-P(sol) + G-CDS(sol) = (2) + (4) -43.182 kcal (6) G-S(sol) free energy of system = (1) + (5) -96.977 kcal 1SCF WAS SPECIFIED, SO GEOMETRY OPTIMIZATION WAS NOT USED Total computer time = 0.68 seconds