Wall clock time and date at job start Sat Apr 11 2020 06:10:38 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 1.53003 * 1 3 3 C 1.52996 * 109.47191 * 2 1 4 4 H 1.08999 * 109.49736 * 305.06222 * 3 2 1 5 5 C 1.53187 * 109.52455 * 65.14594 * 3 2 1 6 6 N 1.46924 * 108.77642 * 174.60153 * 5 3 2 7 7 C 1.34787 * 120.63033 * 126.66473 * 6 5 3 8 8 O 1.21282 * 119.99956 * 359.72115 * 7 6 5 9 9 C 1.50697 * 119.99793 * 179.72182 * 7 6 5 10 10 O 1.42900 * 109.46799 * 179.97438 * 9 7 6 11 11 C 1.42900 * 113.99803 * 180.02562 * 10 9 7 12 12 C 1.53184 * 109.54408 * 269.82078 * 11 10 9 13 13 C 1.53099 * 109.16024 * 183.24536 * 12 11 10 14 14 O 1.42903 * 109.48687 * 57.47029 * 13 12 11 15 15 C 1.42894 * 114.10074 * 298.88880 * 14 13 12 16 16 C 1.53100 * 109.41213 * 61.16105 * 15 14 13 17 17 C 1.46926 * 118.73991 * 306.38981 * 6 5 3 18 18 C 1.53187 * 108.77227 * 53.60881 * 17 6 5 19 19 C 1.53038 * 109.31606 * 305.36475 * 18 17 6 20 20 H 1.09007 * 109.46048 * 301.34968 * 19 18 17 21 21 N 1.46499 * 109.46104 * 181.37516 * 19 18 17 22 22 C 1.36936 * 120.00049 * 85.00074 * 21 19 18 23 23 H 1.08002 * 119.99862 * 0.02562 * 22 21 19 24 24 C 1.38813 * 120.00070 * 179.97438 * 22 21 19 25 25 N 1.31625 * 119.99790 * 359.97438 * 24 22 21 26 26 Si 1.86800 * 120.00084 * 180.02562 * 24 22 21 27 27 H 1.48497 * 109.47236 * 90.00232 * 26 24 22 28 28 H 1.48500 * 109.46736 * 209.99984 * 26 24 22 29 29 H 1.48500 * 109.47005 * 329.99887 * 26 24 22 30 30 H 1.09004 * 109.47099 * 179.97438 * 1 2 3 31 31 H 1.08998 * 109.47415 * 300.00197 * 1 2 3 32 32 H 1.08997 * 109.46872 * 59.99973 * 1 2 3 33 33 H 1.08994 * 109.46939 * 239.99716 * 2 1 3 34 34 H 1.08997 * 109.46872 * 120.00027 * 2 1 3 35 35 H 1.09003 * 109.59079 * 54.81302 * 5 3 2 36 36 H 1.09002 * 109.58636 * 294.38696 * 5 3 2 37 37 H 1.08997 * 109.47228 * 299.99525 * 9 7 6 38 38 H 1.08997 * 109.47248 * 60.00068 * 9 7 6 39 39 H 1.08994 * 109.54369 * 30.00002 * 11 10 9 40 40 H 1.09000 * 109.51849 * 303.06306 * 12 11 10 41 41 H 1.09003 * 109.52172 * 63.24663 * 12 11 10 42 42 H 1.09005 * 109.40290 * 297.49057 * 13 12 11 43 43 H 1.08994 * 109.48558 * 177.50458 * 13 12 11 44 44 H 1.08994 * 109.48565 * 301.18034 * 15 14 13 45 45 H 1.08998 * 109.48201 * 181.13653 * 15 14 13 46 46 H 1.09007 * 109.51887 * 182.48608 * 16 15 14 47 47 H 1.08996 * 109.57359 * 62.32899 * 16 15 14 48 48 H 1.09002 * 109.58798 * 173.39259 * 17 6 5 49 49 H 1.08996 * 109.58371 * 293.82241 * 17 6 5 50 50 H 1.08999 * 109.50002 * 65.31872 * 18 17 6 51 51 H 1.09001 * 109.49774 * 185.38216 * 18 17 6 52 52 H 0.96996 * 119.99845 * 264.98981 * 21 19 18 53 53 H 0.97002 * 119.99690 * 179.97438 * 25 24 22 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 2.0400 1.4425 0.0000 4 1 1.6048 1.9822 -0.8410 5 6 1.6386 2.1274 1.3101 6 7 2.2451 3.4650 1.3495 7 6 1.4864 4.5568 1.5714 8 8 0.2904 4.4409 1.7358 9 6 2.1244 5.9214 1.6152 10 8 1.1210 6.9085 1.8619 11 6 1.6230 8.2451 1.9222 12 6 2.0079 8.5832 3.3659 13 6 2.4679 10.0419 3.4348 14 8 1.4263 10.8934 2.9529 15 6 1.0594 10.6541 1.5928 16 6 0.5406 9.2208 1.4503 17 6 3.6952 3.5894 1.1487 18 6 4.0736 2.8881 -0.1596 19 6 3.5653 1.4450 -0.1257 20 1 4.0009 0.9264 0.7285 21 7 3.9540 0.7614 -1.3618 22 6 5.1916 0.1845 -1.4650 23 1 5.8809 0.2330 -0.6350 24 6 5.5597 -0.4637 -2.6360 25 7 4.7190 -0.5241 -3.6470 26 14 7.2477 -1.2514 -2.7766 27 1 7.1767 -2.6602 -2.3126 28 1 7.6928 -1.2186 -4.1929 29 1 8.2154 -0.5015 -1.9360 30 1 -0.3633 -1.0277 -0.0005 31 1 -0.3634 0.5138 0.8899 32 1 -0.3633 0.5138 -0.8900 33 1 1.8933 -0.5139 -0.8899 34 1 1.8933 -0.5138 0.8900 35 1 1.9965 1.5389 2.1548 36 1 0.5533 2.2168 1.3580 37 1 2.8666 5.9501 2.4129 38 1 2.6087 6.1269 0.6606 39 1 2.4995 8.3346 1.2806 40 1 1.1437 8.4440 4.0153 41 1 2.8173 7.9289 3.6898 42 1 3.3573 10.1706 2.8179 43 1 2.7010 10.3012 4.4674 44 1 1.9302 10.7909 0.9518 45 1 0.2776 11.3544 1.2986 46 1 0.3016 9.0221 0.4055 47 1 -0.3546 9.0942 2.0592 48 1 3.9670 4.6434 1.0901 49 1 4.2208 3.1200 1.9802 50 1 3.6193 3.4142 -0.9991 51 1 5.1577 2.8898 -0.2729 52 1 3.3347 0.7174 -2.1070 53 1 4.9764 -0.9767 -4.4654 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 ZINC001037928319.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 06:10:38 Heat of formation + Delta-G solvation = -126.825952 kcal Electronic energy + Delta-G solvation = -30775.001532 eV Core-core repulsion = 26646.539687 eV Total energy + Delta-G solvation = -4128.461845 eV No. of doubly occupied orbitals = 66 Molecular weight (most abundant/longest-lived isotopes) = 340.220 amu Computer time = 0.81 seconds Orbital eigenvalues (eV) -40.37370 -39.79459 -38.11756 -37.19686 -34.78502 -33.82964 -32.86045 -31.76705 -31.55833 -29.63695 -29.45659 -27.62897 -25.01280 -24.45151 -23.99773 -23.78500 -22.77297 -20.88739 -20.81788 -19.96101 -19.04508 -17.74025 -17.12916 -16.72037 -16.56769 -16.49426 -16.09887 -15.60270 -15.21513 -15.02092 -14.76792 -14.28807 -14.05923 -13.90244 -13.74654 -13.70997 -13.34603 -13.23935 -12.99566 -12.85691 -12.76097 -12.58245 -12.12509 -11.86694 -11.78949 -11.67333 -11.65379 -11.31549 -11.27365 -10.97759 -10.89386 -10.80790 -10.74009 -10.37789 -10.23967 -10.18077 -10.12422 -9.88050 -9.79529 -9.63538 -9.61888 -8.94613 -8.52085 -7.01206 -5.81919 -3.10861 2.59676 2.64991 3.38729 3.42923 3.43980 3.45871 3.59549 4.29551 4.32568 4.51131 4.52923 4.53663 4.67261 4.77730 4.80129 4.92484 4.98417 5.00075 5.07034 5.18357 5.20846 5.22136 5.25374 5.29374 5.41054 5.41435 5.50926 5.56592 5.58579 5.65436 5.66086 5.73787 5.80299 5.87332 5.97359 6.09468 6.12527 6.26732 6.32332 6.36464 6.42734 6.50422 6.63787 6.74929 6.77891 6.82603 6.93574 7.01227 7.44247 7.64047 8.20166 8.36177 9.47700 10.04932 10.39780 11.40407 Molecular weight = 340.22amu Principal moments of inertia in cm(-1) A = 0.015211 B = 0.002281 C = 0.002086 Principal moments of inertia in units of 10**(-40)*gram-cm**2 A = 1840.328612 B =12271.990941 C =13420.092204 Net atomic charges, atomic populations, and dipole contributions calculated with CM2 Atom NO. Type Charge No. of electrons 1 C -0.153 4.153 2 C -0.112 4.112 3 C -0.104 4.104 4 H 0.070 0.930 5 C 0.121 3.879 6 N -0.606 5.606 7 C 0.515 3.485 8 O -0.527 6.527 9 C 0.045 3.955 10 O -0.353 6.353 11 C 0.087 3.913 12 C -0.180 4.180 13 C 0.064 3.936 14 O -0.382 6.382 15 C 0.064 3.936 16 C -0.154 4.154 17 C 0.106 3.894 18 C -0.152 4.152 19 C 0.184 3.816 20 H 0.048 0.952 21 N -0.720 5.720 22 C -0.239 4.239 23 H 0.070 0.930 24 C -0.012 4.012 25 N -0.931 5.931 26 Si 0.905 3.095 27 H -0.290 1.290 28 H -0.292 1.292 29 H -0.283 1.283 30 H 0.049 0.951 31 H 0.049 0.951 32 H 0.051 0.949 33 H 0.084 0.916 34 H 0.057 0.943 35 H 0.066 0.934 36 H 0.091 0.909 37 H 0.077 0.923 38 H 0.081 0.919 39 H 0.064 0.936 40 H 0.083 0.917 41 H 0.076 0.924 42 H 0.052 0.948 43 H 0.098 0.902 44 H 0.053 0.947 45 H 0.100 0.900 46 H 0.082 0.918 47 H 0.083 0.917 48 H 0.073 0.927 49 H 0.070 0.930 50 H 0.060 0.940 51 H 0.077 0.923 52 H 0.384 0.616 53 H 0.255 0.745 For the charges calculated by CM2: Dipole moment (debyes) X Y Z Total from point charges -4.638 18.246 12.869 22.804 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 -0.210 4.210 2 C -0.150 4.150 3 C -0.124 4.124 4 H 0.088 0.912 5 C -0.001 4.001 6 N -0.340 5.340 7 C 0.302 3.698 8 O -0.403 6.403 9 C -0.035 4.035 10 O -0.271 6.271 11 C 0.029 3.971 12 C -0.218 4.218 13 C -0.013 4.013 14 O -0.301 6.301 15 C -0.012 4.012 16 C -0.191 4.191 17 C -0.018 4.018 18 C -0.194 4.194 19 C 0.073 3.927 20 H 0.066 0.934 21 N -0.360 5.360 22 C -0.370 4.370 23 H 0.088 0.912 24 C -0.208 4.208 25 N -0.579 5.579 26 Si 0.736 3.264 27 H -0.218 1.218 28 H -0.218 1.218 29 H -0.208 1.208 30 H 0.069 0.931 31 H 0.068 0.932 32 H 0.070 0.930 33 H 0.102 0.898 34 H 0.076 0.924 35 H 0.084 0.916 36 H 0.109 0.891 37 H 0.095 0.905 38 H 0.098 0.902 39 H 0.082 0.918 40 H 0.102 0.898 41 H 0.094 0.906 42 H 0.070 0.930 43 H 0.116 0.884 44 H 0.071 0.929 45 H 0.119 0.881 46 H 0.101 0.899 47 H 0.102 0.898 48 H 0.091 0.909 49 H 0.088 0.912 50 H 0.079 0.921 51 H 0.095 0.905 52 H 0.218 0.782 53 H 0.065 0.935 Dipole moment (debyes) X Y Z Total from point charges -5.390 18.200 13.098 23.062 hybrid contribution 1.409 -0.711 -0.700 1.726 sum -3.982 17.489 12.397 21.804 Atomic orbital electron populations 1.21847 0.96777 1.01063 1.01346 1.21448 0.94411 0.95627 1.03483 1.21786 0.97620 0.96325 0.96717 0.91181 1.21759 0.99511 0.81031 0.97845 1.48112 1.08532 1.06629 1.70763 1.20114 0.87103 0.85434 0.77140 1.90703 1.14620 1.86176 1.48834 1.22312 0.91446 0.88004 1.01738 1.88069 1.32226 1.14105 1.92734 1.22160 0.96733 0.82651 0.95569 1.22759 1.03198 0.97575 0.98286 1.22557 0.89673 0.88693 1.00369 1.87947 1.55811 1.58565 1.27781 1.22595 0.99897 0.95471 0.83287 1.22293 0.99511 0.94048 1.03278 1.21901 0.79440 1.00866 0.99563 1.22697 1.02274 0.99435 0.94959 1.20178 0.90812 0.90444 0.91253 0.93376 1.42411 1.16519 1.64380 1.12716 1.19202 0.91820 1.27396 0.98582 0.91248 1.24735 0.98150 1.01504 0.96455 1.69661 1.35224 1.48264 1.04774 0.86228 0.83991 0.79363 0.76804 1.21751 1.21846 1.20832 0.93144 0.93199 0.92980 0.89760 0.92443 0.91577 0.89081 0.90476 0.90164 0.91830 0.89846 0.90578 0.93011 0.88435 0.92914 0.88144 0.89908 0.89818 0.90878 0.91202 0.92141 0.90462 0.78175 0.93498 Number of geometries 1 Number of calculations of the screened coulomb radii 1 The total number of SCF iterations 14. 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 -2.13 9.67 37.16 0.36 -1.77 16 2 C -0.11 -1.78 5.31 -26.73 -0.14 -1.93 16 3 C -0.10 -1.68 1.92 -90.50 -0.17 -1.85 16 4 H 0.07 1.23 8.14 -51.93 -0.42 0.80 16 5 C 0.12 1.74 5.33 -3.71 -0.02 1.72 16 6 N -0.61 -8.28 2.97 -172.77 -0.51 -8.79 16 7 C 0.52 7.55 7.78 -10.98 -0.09 7.47 16 8 O -0.53 -9.81 15.91 -14.36 -0.23 -10.04 16 9 C 0.04 0.49 4.58 36.00 0.16 0.66 16 10 O -0.35 -4.42 9.53 -55.14 -0.53 -4.94 16 11 C 0.09 0.78 2.69 -26.54 -0.07 0.71 16 12 C -0.18 -1.41 5.77 -26.59 -0.15 -1.56 16 13 C 0.06 0.44 6.84 37.21 0.25 0.69 16 14 O -0.38 -3.38 10.77 -35.23 -0.38 -3.76 16 15 C 0.06 0.45 6.84 37.21 0.25 0.70 16 16 C -0.15 -1.28 5.79 -26.59 -0.15 -1.43 16 17 C 0.11 1.26 6.34 -3.71 -0.02 1.23 16 18 C -0.15 -2.38 5.66 -26.62 -0.15 -2.53 16 19 C 0.18 3.32 2.19 -67.89 -0.15 3.17 16 20 H 0.05 0.89 8.08 -51.92 -0.42 0.47 16 21 N -0.72 -16.72 4.33 -53.38 -0.23 -16.95 16 22 C -0.24 -6.22 9.93 -15.06 -0.15 -6.37 16 23 H 0.07 1.75 7.83 -52.49 -0.41 1.34 16 24 C -0.01 -0.34 5.50 -17.43 -0.10 -0.43 16 25 N -0.93 -27.18 13.06 55.49 0.72 -26.46 16 26 Si 0.90 21.63 29.55 -169.99 -5.02 16.61 16 27 H -0.29 -6.96 7.11 56.52 0.40 -6.56 16 28 H -0.29 -7.11 7.11 56.52 0.40 -6.70 16 29 H -0.28 -6.55 7.11 56.52 0.40 -6.15 16 30 H 0.05 0.65 8.14 -51.93 -0.42 0.23 16 31 H 0.05 0.65 6.70 -51.93 -0.35 0.30 16 32 H 0.05 0.74 8.14 -51.93 -0.42 0.31 16 33 H 0.08 1.61 7.21 -51.93 -0.37 1.24 16 34 H 0.06 0.88 8.14 -51.93 -0.42 0.46 16 35 H 0.07 0.88 8.14 -51.93 -0.42 0.46 16 36 H 0.09 1.40 5.73 -51.93 -0.30 1.10 16 37 H 0.08 0.66 7.78 -51.93 -0.40 0.25 16 38 H 0.08 0.75 7.63 -51.93 -0.40 0.36 16 39 H 0.06 0.47 7.79 -51.93 -0.40 0.07 16 40 H 0.08 0.77 8.14 -51.93 -0.42 0.34 16 41 H 0.08 0.51 7.97 -51.93 -0.41 0.10 16 42 H 0.05 0.29 8.14 -51.93 -0.42 -0.13 16 43 H 0.10 0.54 8.14 -51.93 -0.42 0.12 16 44 H 0.05 0.31 8.14 -51.93 -0.42 -0.12 16 45 H 0.10 0.56 8.14 -51.93 -0.42 0.14 16 46 H 0.08 0.65 8.14 -51.93 -0.42 0.23 16 47 H 0.08 0.80 8.14 -51.93 -0.42 0.37 16 48 H 0.07 0.68 5.94 -51.93 -0.31 0.37 16 49 H 0.07 0.76 8.14 -51.93 -0.42 0.34 16 50 H 0.06 1.01 8.14 -51.93 -0.42 0.59 16 51 H 0.08 1.28 8.14 -51.93 -0.42 0.85 16 52 H 0.38 9.71 7.51 -40.82 -0.31 9.41 16 53 H 0.26 7.27 8.31 -40.82 -0.34 6.93 16 LS Contribution 410.21 15.07 6.18 6.18 Total: -1.00 -32.25 410.21 -9.89 -42.15 By element: Atomic # 1 Polarization: 17.09 SS G_CDS: -9.56 Total: 7.53 kcal Atomic # 6 Polarization: -1.19 SS G_CDS: -0.33 Total: -1.53 kcal Atomic # 7 Polarization: -52.18 SS G_CDS: -0.02 Total: -52.20 kcal Atomic # 8 Polarization: -17.61 SS G_CDS: -1.13 Total: -18.74 kcal Atomic # 14 Polarization: 21.63 SS G_CDS: -5.02 Total: 16.61 kcal Total LS contribution 6.18 Total: 6.18 kcal Total: -32.25 -9.89 -42.15 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. ZINC001037928319.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 -84.680 kcal (2) G-P(sol) polarization free energy of solvation -32.254 kcal (3) G-ENP(sol) elect.-nuc.-pol. free energy of system -116.935 kcal (4) G-CDS(sol) cavity-dispersion-solvent structure free energy -9.891 kcal (5) G-P-CDS(sol) = G-P(sol) + G-CDS(sol) = (2) + (4) -42.146 kcal (6) G-S(sol) free energy of system = (1) + (5) -126.826 kcal 1SCF WAS SPECIFIED, SO GEOMETRY OPTIMIZATION WAS NOT USED Total computer time = 0.81 seconds