Wall clock time and date at job start Tue Mar 31 2020 20:24:28 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 C 1.53002 * 109.47462 * 2 1 4 4 H 1.09005 * 109.46713 * 299.09505 * 3 2 1 5 5 C 1.50690 * 109.47481 * 179.09114 * 3 2 1 6 6 H 1.07997 * 120.00135 * 245.66343 * 5 3 2 7 7 C 1.37883 * 120.00021 * 65.66535 * 5 3 2 8 8 N 1.31515 * 119.99841 * 359.97438 * 7 5 3 9 9 Si 1.86799 * 120.00067 * 180.02562 * 7 5 3 10 10 H 1.48495 * 109.47604 * 59.99696 * 9 7 5 11 11 H 1.48495 * 109.47075 * 180.02562 * 9 7 5 12 12 H 1.48505 * 109.47021 * 299.99725 * 9 7 5 13 13 N 1.46900 * 109.46910 * 59.09020 * 3 2 1 14 14 C 1.46645 * 110.99901 * 66.26468 * 13 3 2 15 15 C 1.53348 * 108.18259 * 186.44123 * 14 13 3 16 16 H 1.08996 * 109.69739 * 56.52526 * 15 14 13 17 17 C 1.50701 * 109.73002 * 177.10699 * 15 14 13 18 18 O 1.21273 * 120.00089 * 84.37195 * 17 15 14 19 19 N 1.34776 * 119.99594 * 264.37535 * 17 15 14 20 20 C 1.47023 * 125.65020 * 4.94843 * 19 17 15 21 21 C 1.54323 * 107.27539 * 180.97240 * 20 19 17 22 22 C 1.55158 * 102.86116 * 22.52941 * 21 20 19 23 23 C 1.47423 * 125.64793 * 185.26739 * 19 17 15 24 24 C 1.52736 * 108.29493 * 296.82277 * 15 14 13 25 25 C 1.53177 * 110.58722 * 60.02567 * 24 15 14 26 26 H 1.08995 * 111.52589 * 73.74333 * 25 24 15 27 27 O 1.44753 * 106.46201 * 196.85871 * 25 24 15 28 28 C 1.43406 * 109.51703 * 89.15753 * 27 25 24 29 29 C 1.54711 * 107.56214 * 4.21661 * 28 27 25 30 30 C 1.44590 * 110.99928 * 193.72331 * 13 3 2 31 31 H 1.09002 * 109.63518 * 57.78547 * 30 13 3 32 32 H 1.09005 * 109.46876 * 60.00313 * 1 2 3 33 33 H 1.09001 * 109.46759 * 179.97438 * 1 2 3 34 34 H 1.08993 * 109.47394 * 299.99943 * 1 2 3 35 35 H 1.09007 * 109.47250 * 239.99977 * 2 1 3 36 36 H 1.09000 * 109.47077 * 120.00399 * 2 1 3 37 37 H 0.97000 * 119.99635 * 180.02562 * 8 7 5 38 38 H 1.08994 * 109.71955 * 66.77068 * 14 13 3 39 39 H 1.09000 * 109.72028 * 306.11216 * 14 13 3 40 40 H 1.08995 * 109.88776 * 300.51977 * 20 19 17 41 41 H 1.09002 * 109.87903 * 61.68524 * 20 19 17 42 42 H 1.08997 * 110.92104 * 264.11178 * 21 20 19 43 43 H 1.08998 * 110.74186 * 140.86084 * 21 20 19 44 44 H 1.09002 * 111.00105 * 206.22842 * 22 21 20 45 45 H 1.09000 * 111.00053 * 82.37825 * 22 21 20 46 46 H 1.09008 * 110.36273 * 274.66820 * 23 19 17 47 47 H 1.08999 * 110.37070 * 36.87847 * 23 19 17 48 48 H 1.09006 * 109.25507 * 180.30833 * 24 15 14 49 49 H 1.08996 * 109.25636 * 299.73733 * 24 15 14 50 50 H 1.09006 * 109.83485 * 244.70820 * 28 27 25 51 51 H 1.09004 * 109.91437 * 123.77328 * 28 27 25 52 52 H 1.08998 * 111.01969 * 262.57408 * 29 28 27 53 53 H 1.09001 * 111.01475 * 138.69432 * 29 28 27 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 6 2.0401 1.4425 0.0000 4 1 1.6900 1.9516 -0.8981 5 6 3.5468 1.4426 0.0225 6 1 4.0740 1.8325 0.8806 7 6 4.2524 0.9448 -1.0524 8 7 3.6104 0.4695 -2.0972 9 14 6.1202 0.9442 -1.0242 10 1 6.5977 0.1336 0.1247 11 1 6.6341 0.3613 -2.2895 12 1 6.6136 2.3380 -0.8856 13 7 1.5325 2.1413 1.1883 14 6 2.1026 1.5744 2.4148 15 6 1.4124 2.2363 3.6136 16 1 0.3344 2.0925 3.5423 17 6 1.9225 1.6273 4.8942 18 8 2.9476 2.0386 5.3951 19 7 1.2396 0.6255 5.4828 20 6 0.0461 -0.0356 4.9349 21 6 -0.4014 -1.0975 5.9614 22 6 0.2230 -0.5828 7.2853 23 6 1.5616 0.0156 6.7858 24 6 1.7355 3.7289 3.5889 25 6 1.2305 4.3678 2.2916 26 1 0.1458 4.4747 2.2942 27 8 1.9131 5.6383 2.1673 28 6 3.1457 5.4526 1.4582 29 6 3.2080 3.9732 1.0097 30 6 1.7183 3.5701 1.0680 31 1 1.2144 3.9308 0.1712 32 1 -0.3633 0.5138 -0.8901 33 1 -0.3633 -1.0277 -0.0005 34 1 -0.3634 0.5138 0.8899 35 1 1.8934 -0.5139 -0.8900 36 1 1.8933 -0.5139 0.8900 37 1 4.1068 0.1190 -2.8532 38 1 3.1733 1.7754 2.4498 39 1 1.9287 0.4986 2.4381 40 1 -0.7477 0.6963 4.7859 41 1 0.2911 -0.5177 3.9886 42 1 -0.0045 -2.0794 5.7038 43 1 -1.4885 -1.1296 6.0346 44 1 0.3974 -1.4043 7.9802 45 1 -0.4029 0.1852 7.7398 46 1 2.3063 -0.7709 6.6627 47 1 1.9228 0.7737 7.4807 48 1 1.2563 4.2145 4.4390 49 1 2.8147 3.8643 3.6598 50 1 3.9870 5.6760 2.1143 51 1 3.1740 6.1052 0.5856 52 1 3.8012 3.3787 1.7045 53 1 3.5964 3.8885 -0.0052 RHF calculation, no. of doubly occupied orbitals= 65 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 ZINC001255167562.mol2 53 1SCF WAS SPECIFIED, SO GEOMETRY OPTIMIZATION WAS NOT USED SCF FIELD WAS ACHIEVED Wall clock time and date at job start Tue Mar 31 2020 20:24:28 Heat of formation + Delta-G solvation = -73.647944 kcal Electronic energy + Delta-G solvation = -32455.390807 eV Core-core repulsion = 28519.690986 eV Total energy + Delta-G solvation = -3935.699822 eV No. of doubly occupied orbitals = 65 Molecular weight (most abundant/longest-lived isotopes) = 336.220 amu Computer time = 0.80 seconds Orbital eigenvalues (eV) -40.66468 -39.53628 -37.36608 -36.77147 -34.05723 -32.26722 -31.69107 -31.43448 -29.50424 -29.35655 -28.68833 -26.69526 -24.55698 -24.15868 -22.60655 -22.43244 -21.40841 -21.26663 -19.74811 -18.96949 -18.22469 -17.10961 -16.61772 -16.48552 -16.07445 -15.69822 -15.25202 -14.78031 -14.46000 -14.29175 -14.01074 -13.71755 -13.50034 -13.25526 -13.20977 -12.99097 -12.93840 -12.50614 -12.40453 -12.27131 -12.11660 -11.78334 -11.57373 -11.45598 -11.39843 -11.30560 -11.14245 -10.98756 -10.97041 -10.83311 -10.59619 -10.44277 -10.26611 -10.08988 -9.94964 -9.69965 -9.47105 -9.44179 -9.16016 -8.89971 -8.60970 -8.43498 -7.24507 -6.06733 -4.15751 2.79278 3.01697 3.25129 3.30596 3.34698 4.17857 4.32532 4.35666 4.42395 4.69400 4.73517 4.91958 5.09270 5.18165 5.19908 5.20633 5.31340 5.41825 5.44961 5.48418 5.52039 5.59283 5.61641 5.67363 5.71170 5.76858 5.79679 5.84611 5.91015 5.95800 6.16028 6.18934 6.27015 6.29611 6.33776 6.35957 6.42308 6.51770 6.57475 6.62094 6.82798 6.97493 6.99573 7.07320 7.24974 7.33973 7.51076 7.56436 7.67121 7.83934 8.03558 8.21715 8.32179 8.36367 8.90912 9.50400 10.95449 Molecular weight = 336.22amu Principal moments of inertia in cm(-1) A = 0.010263 B = 0.004731 C = 0.004070 Principal moments of inertia in units of 10**(-40)*gram-cm**2 A = 2727.591502 B = 5916.458212 C = 6878.257583 Net atomic charges, atomic populations, and dipole contributions calculated with CM2 Atom NO. Type Charge No. of electrons 1 C -0.139 4.139 2 C -0.105 4.105 3 C 0.220 3.780 4 H 0.044 0.956 5 C -0.546 4.546 6 H 0.064 0.936 7 C 0.072 3.928 8 N -0.885 5.885 9 Si 0.881 3.119 10 H -0.278 1.278 11 H -0.287 1.287 12 H -0.277 1.277 13 N -0.527 5.527 14 C 0.083 3.917 15 C -0.101 4.101 16 H 0.093 0.907 17 C 0.541 3.459 18 O -0.540 6.540 19 N -0.622 5.622 20 C 0.099 3.901 21 C -0.132 4.132 22 C -0.133 4.133 23 C 0.104 3.896 24 C -0.117 4.117 25 C 0.087 3.913 26 H 0.103 0.897 27 O -0.388 6.388 28 C 0.044 3.956 29 C -0.169 4.169 30 C 0.082 3.918 31 H 0.084 0.916 32 H 0.039 0.961 33 H 0.024 0.976 34 H 0.050 0.950 35 H 0.081 0.919 36 H 0.033 0.967 37 H 0.262 0.738 38 H 0.051 0.949 39 H 0.075 0.925 40 H 0.070 0.930 41 H 0.075 0.925 42 H 0.077 0.923 43 H 0.081 0.919 44 H 0.082 0.918 45 H 0.074 0.926 46 H 0.065 0.935 47 H 0.074 0.926 48 H 0.060 0.940 49 H 0.076 0.924 50 H 0.055 0.945 51 H 0.064 0.936 52 H 0.077 0.923 53 H 0.096 0.904 For the charges calculated by CM2: Dipole moment (debyes) X Y Z Total from point charges -9.407 -0.872 12.558 15.714 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 -0.196 4.196 2 C -0.144 4.144 3 C 0.114 3.886 4 H 0.062 0.938 5 C -0.585 4.585 6 H 0.082 0.918 7 C -0.131 4.131 8 N -0.523 5.523 9 Si 0.709 3.291 10 H -0.204 1.204 11 H -0.213 1.213 12 H -0.203 1.203 13 N -0.250 5.250 14 C -0.045 4.045 15 C -0.123 4.123 16 H 0.111 0.889 17 C 0.330 3.670 18 O -0.417 6.417 19 N -0.358 5.358 20 C -0.024 4.024 21 C -0.170 4.170 22 C -0.172 4.172 23 C -0.019 4.019 24 C -0.155 4.155 25 C 0.030 3.970 26 H 0.121 0.879 27 O -0.307 6.307 28 C -0.033 4.033 29 C -0.208 4.208 30 C -0.029 4.029 31 H 0.102 0.898 32 H 0.058 0.942 33 H 0.044 0.956 34 H 0.069 0.931 35 H 0.100 0.900 36 H 0.052 0.948 37 H 0.072 0.928 38 H 0.069 0.931 39 H 0.094 0.906 40 H 0.088 0.912 41 H 0.094 0.906 42 H 0.096 0.904 43 H 0.100 0.900 44 H 0.100 0.900 45 H 0.093 0.907 46 H 0.084 0.916 47 H 0.093 0.907 48 H 0.078 0.922 49 H 0.095 0.905 50 H 0.073 0.927 51 H 0.082 0.918 52 H 0.096 0.904 53 H 0.115 0.885 Dipole moment (debyes) X Y Z Total from point charges -9.330 -0.536 12.679 15.751 hybrid contribution 2.124 -0.217 -0.206 2.145 sum -7.206 -0.753 12.474 14.425 Atomic orbital electron populations 1.21713 0.98618 0.98421 1.00851 1.21545 0.92328 0.99075 1.01417 1.19256 0.92362 0.90472 0.86461 0.93764 1.21853 0.92281 1.41388 1.02983 0.91769 1.24862 0.97815 0.94986 0.95464 1.69894 1.35286 1.40698 1.06388 0.86831 0.86505 0.78466 0.77308 1.20352 1.21305 1.20253 1.60937 1.59162 1.01137 1.03776 1.21759 0.97196 0.98374 0.87213 1.21347 1.02075 0.96364 0.92524 0.88880 1.20467 0.83002 0.77869 0.85672 1.90673 1.23599 1.61844 1.65558 1.48545 1.30000 1.36045 1.21205 1.22068 0.87519 0.95089 0.97716 1.22638 1.01297 0.98622 0.94416 1.22784 0.96213 1.00830 0.97326 1.22183 0.96986 0.97564 0.85127 1.21839 1.02980 0.92657 0.98008 1.23028 0.96833 0.83272 0.93900 0.87885 1.88611 1.34558 1.30229 1.77262 1.23239 0.86462 0.98176 0.95396 1.23758 0.99633 0.93311 1.04146 1.22185 0.94075 0.89769 0.96857 0.89827 0.94169 0.95642 0.93080 0.90020 0.94818 0.92843 0.93091 0.90623 0.91170 0.90642 0.90427 0.89989 0.89958 0.90690 0.91623 0.90705 0.92154 0.90524 0.92661 0.91790 0.90408 0.88513 Number of geometries 1 Number of calculations of the screened coulomb radii 1 The total number of SCF iterations 12. 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 -0.14 -2.48 9.75 37.16 0.36 -2.12 16 2 C -0.11 -2.25 5.07 -26.73 -0.14 -2.38 16 3 C 0.22 4.87 1.62 -68.87 -0.11 4.76 16 4 H 0.04 1.11 7.94 -51.93 -0.41 0.70 16 5 C -0.55 -13.33 5.64 -34.44 -0.19 -13.52 16 6 H 0.06 1.59 4.17 -52.49 -0.22 1.38 16 7 C 0.07 1.84 5.33 -17.82 -0.09 1.75 16 8 N -0.88 -23.64 11.75 55.43 0.65 -22.99 16 9 Si 0.88 20.55 29.54 -169.99 -5.02 15.53 16 10 H -0.28 -6.58 7.11 56.52 0.40 -6.18 16 11 H -0.29 -6.73 7.11 56.52 0.40 -6.33 16 12 H -0.28 -6.45 7.11 56.52 0.40 -6.04 16 13 N -0.53 -9.85 3.63 -220.34 -0.80 -10.65 16 14 C 0.08 1.52 3.91 -3.78 -0.01 1.50 16 15 C -0.10 -1.59 2.31 -91.73 -0.21 -1.80 16 16 H 0.09 1.30 6.92 -51.93 -0.36 0.94 16 17 C 0.54 8.89 6.87 -10.98 -0.08 8.81 16 18 O -0.54 -10.82 16.56 5.56 0.09 -10.72 16 19 N -0.62 -8.17 3.33 -170.52 -0.57 -8.74 16 20 C 0.10 1.00 6.20 -3.06 -0.02 0.98 16 21 C -0.13 -0.98 6.95 -24.90 -0.17 -1.15 16 22 C -0.13 -1.00 7.08 -24.58 -0.17 -1.18 16 23 C 0.10 1.14 6.89 -2.53 -0.02 1.13 16 24 C -0.12 -1.91 4.12 -26.78 -0.11 -2.02 16 25 C 0.09 1.42 4.21 -26.12 -0.11 1.31 16 26 H 0.10 1.50 8.14 -51.93 -0.42 1.08 16 27 O -0.39 -6.75 10.95 -35.23 -0.39 -7.13 16 28 C 0.04 0.74 7.43 38.06 0.28 1.03 16 29 C -0.17 -3.18 3.98 -25.08 -0.10 -3.28 16 30 C 0.08 1.47 2.70 -67.68 -0.18 1.29 16 31 H 0.08 1.55 8.03 -51.93 -0.42 1.13 16 32 H 0.04 0.73 8.14 -51.93 -0.42 0.31 16 33 H 0.02 0.41 8.14 -51.93 -0.42 -0.02 16 34 H 0.05 0.85 7.58 -51.93 -0.39 0.46 16 35 H 0.08 1.99 6.55 -51.93 -0.34 1.65 16 36 H 0.03 0.71 6.48 -51.93 -0.34 0.38 16 37 H 0.26 6.82 8.31 -40.82 -0.34 6.48 16 38 H 0.05 1.09 5.05 -51.93 -0.26 0.82 16 39 H 0.08 1.41 6.26 -51.93 -0.32 1.08 16 40 H 0.07 0.65 7.63 -51.93 -0.40 0.25 16 41 H 0.08 0.82 8.14 -51.93 -0.42 0.40 16 42 H 0.08 0.55 8.14 -51.93 -0.42 0.13 16 43 H 0.08 0.48 8.14 -51.93 -0.42 0.06 16 44 H 0.08 0.49 8.14 -51.93 -0.42 0.06 16 45 H 0.07 0.54 8.14 -51.93 -0.42 0.12 16 46 H 0.07 0.73 8.14 -51.92 -0.42 0.30 16 47 H 0.07 0.88 8.09 -51.93 -0.42 0.46 16 48 H 0.06 0.93 8.14 -51.93 -0.42 0.51 16 49 H 0.08 1.43 6.79 -51.93 -0.35 1.08 16 50 H 0.06 0.89 8.14 -51.93 -0.42 0.47 16 51 H 0.06 0.99 8.14 -51.93 -0.42 0.57 16 52 H 0.08 1.59 4.82 -51.93 -0.25 1.34 16 53 H 0.10 2.00 7.20 -51.93 -0.37 1.63 16 LS Contribution 386.67 15.07 5.83 5.83 Total: -1.00 -28.21 386.67 -10.35 -38.56 By element: Atomic # 1 Polarization: 14.29 SS G_CDS: -9.07 Total: 5.22 kcal Atomic # 6 Polarization: -3.81 SS G_CDS: -1.08 Total: -4.89 kcal Atomic # 7 Polarization: -41.67 SS G_CDS: -0.72 Total: -42.38 kcal Atomic # 8 Polarization: -17.56 SS G_CDS: -0.29 Total: -17.86 kcal Atomic # 14 Polarization: 20.55 SS G_CDS: -5.02 Total: 15.53 kcal Total LS contribution 5.83 Total: 5.83 kcal Total: -28.21 -10.35 -38.56 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. ZINC001255167562.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 -35.092 kcal (2) G-P(sol) polarization free energy of solvation -28.206 kcal (3) G-ENP(sol) elect.-nuc.-pol. free energy of system -63.298 kcal (4) G-CDS(sol) cavity-dispersion-solvent structure free energy -10.350 kcal (5) G-P-CDS(sol) = G-P(sol) + G-CDS(sol) = (2) + (4) -38.556 kcal (6) G-S(sol) free energy of system = (1) + (5) -73.648 kcal 1SCF WAS SPECIFIED, SO GEOMETRY OPTIMIZATION WAS NOT USED Total computer time = 0.81 seconds