Wall clock time and date at job start Sat Apr 11 2020 06:13:36 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 1.52995 * 1 3 3 H 1.08993 * 109.99816 * 2 1 4 4 C 1.54327 * 109.88277 * 238.89801 * 2 1 3 5 5 C 1.55154 * 102.94290 * 218.39145 * 4 2 1 6 6 H 1.09002 * 111.00378 * 277.42832 * 5 4 2 7 7 N 1.46900 * 111.00320 * 153.61398 * 5 4 2 8 8 C 1.46904 * 110.99917 * 158.17965 * 7 5 4 9 9 C 1.52995 * 109.46963 * 180.02562 * 8 7 5 10 10 C 1.52999 * 109.47044 * 294.99896 * 9 8 7 11 11 C 1.53000 * 109.47139 * 180.02562 * 10 9 8 12 12 C 1.52997 * 109.47523 * 59.99782 * 11 10 9 13 13 C 1.52999 * 109.47091 * 300.00247 * 12 11 10 14 14 C 1.52997 * 109.47305 * 174.99869 * 9 8 7 15 15 C 1.54915 * 101.58176 * 35.50368 * 5 4 2 16 16 N 1.47029 * 109.88243 * 121.09352 * 2 1 3 17 17 C 1.34773 * 125.64745 * 298.31299 * 16 2 1 18 18 O 1.21289 * 120.00133 * 0.02562 * 17 16 2 19 19 C 1.50701 * 120.00085 * 179.97438 * 17 16 2 20 20 S 1.81006 * 109.47199 * 179.97438 * 19 17 16 21 21 C 1.76195 * 99.99818 * 179.97438 * 20 19 17 22 22 H 1.08003 * 120.00468 * 0.02562 * 21 20 19 23 23 C 1.38805 * 119.99749 * 179.97438 * 21 20 19 24 24 N 1.31624 * 119.99960 * 0.02562 * 23 21 20 25 25 Si 1.86804 * 119.99717 * 179.97438 * 23 21 20 26 26 H 1.48500 * 109.47271 * 0.02562 * 25 23 21 27 27 H 1.48500 * 109.46764 * 120.00301 * 25 23 21 28 28 H 1.48498 * 109.47011 * 240.00007 * 25 23 21 29 29 H 1.09008 * 109.47549 * 181.10192 * 1 2 3 30 30 H 1.09001 * 109.47247 * 301.09809 * 1 2 3 31 31 H 1.09005 * 109.47241 * 61.09724 * 1 2 3 32 32 H 1.09004 * 110.71649 * 100.02728 * 4 2 1 33 33 H 1.08997 * 110.87056 * 336.82650 * 4 2 1 34 34 H 1.00899 * 111.00265 * 282.13684 * 7 5 4 35 35 H 1.09002 * 109.46904 * 299.99983 * 8 7 5 36 36 H 1.08997 * 109.46968 * 59.99918 * 8 7 5 37 37 H 1.08994 * 109.47523 * 55.00004 * 9 8 7 38 38 H 1.09001 * 109.47163 * 299.99976 * 10 9 8 39 39 H 1.08995 * 109.47286 * 60.00572 * 10 9 8 40 40 H 1.09008 * 109.47093 * 300.00048 * 11 10 9 41 41 H 1.09004 * 109.47239 * 180.02562 * 11 10 9 42 42 H 1.08993 * 109.47533 * 180.02562 * 12 11 10 43 43 H 1.09001 * 109.47008 * 60.00209 * 12 11 10 44 44 H 1.09001 * 109.47163 * 299.99866 * 13 12 11 45 45 H 1.09005 * 109.47023 * 179.97438 * 13 12 11 46 46 H 1.08996 * 109.47154 * 300.00102 * 14 9 8 47 47 H 1.09001 * 109.47008 * 59.99959 * 14 9 8 48 48 H 1.08995 * 110.36257 * 81.82999 * 15 5 4 49 49 H 1.08997 * 110.36405 * 204.14718 * 15 5 4 50 50 H 1.08997 * 109.47078 * 299.99511 * 19 17 16 51 51 H 1.08999 * 109.46736 * 60.00000 * 19 17 16 52 52 H 0.97003 * 119.99966 * 179.97438 * 24 23 21 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 1.5299 0.0000 0.0000 3 1 1.9027 1.0242 0.0000 4 6 2.0548 -0.7497 -1.2427 5 6 3.2875 -1.5144 -0.6922 6 1 4.1653 -0.8690 -0.6603 7 7 3.5543 -2.7226 -1.4841 8 6 4.9491 -3.1566 -1.3285 9 6 5.1883 -4.4141 -2.1665 10 6 4.3428 -5.5634 -1.6143 11 6 4.5825 -6.8212 -2.4519 12 6 6.0631 -7.2014 -2.3890 13 6 6.9087 -6.0520 -2.9412 14 6 6.6689 -4.7946 -2.1041 15 6 2.8144 -1.8794 0.7370 16 7 2.0300 -0.7141 1.1840 17 6 1.8086 -0.3611 2.4657 18 8 1.1453 0.6225 2.7180 19 6 2.3843 -1.1892 3.5855 20 16 1.9154 -0.4628 5.1757 21 6 2.6975 -1.5980 6.2731 22 1 3.2568 -2.4331 5.8777 23 6 2.5957 -1.4185 7.6457 24 7 1.9145 -0.4005 8.1275 25 14 3.4243 -2.6224 8.8091 26 1 4.1215 -3.6712 8.0221 27 1 4.4104 -1.8983 9.6508 28 1 2.4003 -3.2544 9.6791 29 1 -0.3634 -1.0275 0.0198 30 1 -0.3634 0.5308 0.8800 31 1 -0.3634 0.4967 -0.8997 32 1 2.3529 -0.0461 -2.0201 33 1 1.3064 -1.4460 -1.6209 34 1 2.9154 -3.4640 -1.2390 35 1 5.6162 -2.3633 -1.6658 36 1 5.1465 -3.3758 -0.2792 37 1 4.9064 -4.2202 -3.2014 38 1 4.6247 -5.7574 -0.5794 39 1 3.2880 -5.2925 -1.6589 40 1 4.3008 -6.6275 -3.4870 41 1 3.9797 -7.6399 -2.0588 42 1 6.2339 -8.0971 -2.9861 43 1 6.3448 -7.3951 -1.3540 44 1 6.6270 -5.8584 -3.9762 45 1 7.9636 -6.3228 -2.8960 46 1 7.2713 -3.9758 -2.4975 47 1 6.9509 -4.9885 -1.0692 48 1 2.1885 -2.7715 0.7130 49 1 3.6715 -2.0339 1.3924 50 1 1.9968 -2.2059 3.5218 51 1 3.4709 -1.2084 3.5015 52 1 1.8431 -0.2752 9.0867 RHF calculation, no. of doubly occupied orbitals= 63 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). S: (AM1): M.J.S. DEWAR, Y.-C. YUAN, INORGANIC CHEM., 29, 589 (1990) 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 ZINC001676710816.mol2 52 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 06:13:36 Heat of formation + Delta-G solvation = -64.945948 kcal Electronic energy + Delta-G solvation = -27557.753008 eV Core-core repulsion = 23874.727353 eV Total energy + Delta-G solvation = -3683.025655 eV No. of doubly occupied orbitals = 63 Molecular weight (most abundant/longest-lived isotopes) = 340.193 amu Computer time = 1.81 seconds Orbital eigenvalues (eV) -40.18449 -39.18041 -37.58696 -35.30441 -32.44495 -32.15530 -31.94694 -31.10783 -29.09187 -28.60495 -25.87086 -25.50264 -25.06141 -23.03582 -22.10705 -21.38393 -20.98771 -20.02934 -18.94321 -17.66976 -17.03561 -16.27943 -16.07576 -15.65794 -14.93355 -14.82644 -14.80782 -14.56402 -14.40470 -14.28402 -14.00013 -13.80016 -13.43374 -13.28572 -13.08611 -12.82490 -12.63096 -12.52908 -12.50921 -12.31922 -12.04703 -11.81151 -11.75701 -11.60579 -11.47119 -11.28565 -11.08846 -11.03934 -10.98097 -10.88660 -10.77015 -10.76708 -10.34280 -10.33315 -9.81951 -9.38499 -9.08796 -8.76197 -8.48046 -8.24130 -6.51477 -6.23086 -3.93611 2.88298 3.06965 3.20160 3.24241 3.29555 3.54724 3.81034 4.18645 4.29060 4.33909 4.39147 4.41656 4.49864 4.74103 4.81770 4.92096 4.98646 5.03001 5.07325 5.09922 5.12111 5.13567 5.15215 5.17483 5.26190 5.34872 5.38723 5.45755 5.46589 5.55551 5.58928 5.61570 5.66518 5.68236 5.74750 5.78124 5.79976 5.84550 5.85527 5.88369 5.91648 5.99884 6.10856 6.11483 6.15955 6.31257 6.55851 6.69965 7.01663 7.58214 7.69303 8.33896 8.57861 9.22235 10.84407 Molecular weight = 340.19amu Principal moments of inertia in cm(-1) A = 0.009132 B = 0.002628 C = 0.002119 Principal moments of inertia in units of 10**(-40)*gram-cm**2 A = 3065.336270 B =10653.619579 C =13208.291186 Net atomic charges, atomic populations, and dipole contributions calculated with CM2 Atom NO. Type Charge No. of electrons 1 C -0.162 4.162 2 C 0.134 3.866 3 H 0.074 0.926 4 C -0.114 4.114 5 C 0.075 3.925 6 H 0.094 0.906 7 N -0.674 5.674 8 C 0.059 3.941 9 C -0.084 4.084 10 C -0.118 4.118 11 C -0.118 4.118 12 C -0.121 4.121 13 C -0.118 4.118 14 C -0.115 4.115 15 C 0.075 3.925 16 N -0.619 5.619 17 C 0.549 3.451 18 O -0.513 6.513 19 C -0.147 4.147 20 S -0.060 6.060 21 C -0.534 4.534 22 H 0.072 0.928 23 C 0.073 3.927 24 N -0.867 5.867 25 Si 0.919 3.081 26 H -0.272 1.272 27 H -0.280 1.280 28 H -0.279 1.279 29 H 0.054 0.946 30 H 0.072 0.928 31 H 0.061 0.939 32 H 0.082 0.918 33 H 0.081 0.919 34 H 0.343 0.657 35 H 0.073 0.927 36 H 0.034 0.966 37 H 0.079 0.921 38 H 0.061 0.939 39 H 0.063 0.937 40 H 0.061 0.939 41 H 0.060 0.940 42 H 0.059 0.941 43 H 0.061 0.939 44 H 0.061 0.939 45 H 0.060 0.940 46 H 0.062 0.938 47 H 0.062 0.938 48 H 0.065 0.935 49 H 0.075 0.925 50 H 0.086 0.914 51 H 0.086 0.914 52 H 0.268 0.732 For the charges calculated by CM2: Dipole moment (debyes) X Y Z Total from point charges 7.076 -10.471 -25.919 28.836 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 -0.220 4.220 2 C 0.031 3.969 3 H 0.092 0.908 4 C -0.152 4.152 5 C -0.036 4.036 6 H 0.112 0.888 7 N -0.305 5.305 8 C -0.070 4.070 9 C -0.103 4.103 10 C -0.156 4.156 11 C -0.156 4.156 12 C -0.159 4.159 13 C -0.156 4.156 14 C -0.153 4.153 15 C -0.051 4.051 16 N -0.357 5.357 17 C 0.337 3.663 18 O -0.386 6.386 19 C -0.297 4.297 20 S 0.167 5.833 21 C -0.683 4.683 22 H 0.090 0.910 23 C -0.136 4.136 24 N -0.502 5.502 25 Si 0.745 3.255 26 H -0.196 1.196 27 H -0.205 1.205 28 H -0.205 1.205 29 H 0.073 0.927 30 H 0.091 0.909 31 H 0.080 0.920 32 H 0.101 0.899 33 H 0.099 0.901 34 H 0.163 0.837 35 H 0.092 0.908 36 H 0.052 0.948 37 H 0.097 0.903 38 H 0.079 0.921 39 H 0.082 0.918 40 H 0.080 0.920 41 H 0.079 0.921 42 H 0.077 0.923 43 H 0.080 0.920 44 H 0.080 0.920 45 H 0.079 0.921 46 H 0.081 0.919 47 H 0.081 0.919 48 H 0.083 0.917 49 H 0.093 0.907 50 H 0.105 0.895 51 H 0.105 0.895 52 H 0.078 0.922 Dipole moment (debyes) X Y Z Total from point charges 6.134 -8.539 -25.875 27.929 hybrid contribution 1.310 -2.375 1.456 3.078 sum 7.444 -10.914 -24.419 27.763 Atomic orbital electron populations 1.22130 0.94749 1.02218 1.02896 1.21538 0.94810 0.96434 0.84151 0.90754 1.22713 0.97023 0.99184 0.96319 1.22788 0.98611 0.92643 0.89551 0.88785 1.60598 1.04774 1.07473 1.57700 1.22093 0.89677 0.97036 0.98175 1.21167 0.95098 0.93584 1.00456 1.21627 0.99696 0.94747 0.99511 1.21506 0.96240 0.97498 1.00331 1.21547 0.95236 0.97833 1.01242 1.21505 0.99510 0.95060 0.99501 1.21542 0.95680 0.97549 1.00505 1.23008 0.95612 0.89565 0.96891 1.48493 1.53840 1.28418 1.04969 1.20001 0.79817 0.85043 0.81424 1.90695 1.38536 1.26885 1.82520 1.23511 1.03496 1.02582 1.00127 1.85398 1.69793 1.37564 0.90562 1.22889 1.38310 1.13960 0.93096 0.90972 1.24995 0.95255 0.95996 0.97355 1.70026 1.38581 1.28046 1.13571 0.86118 0.79024 0.80254 0.80107 1.19641 1.20540 1.20532 0.92690 0.90885 0.91975 0.89912 0.90080 0.83672 0.90824 0.94769 0.90264 0.92055 0.91809 0.92003 0.92127 0.92258 0.92039 0.92032 0.92139 0.91911 0.91942 0.91656 0.90653 0.89525 0.89549 0.92220 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 -0.16 -2.01 9.10 37.15 0.34 -1.67 16 2 C 0.13 1.65 3.46 -66.95 -0.23 1.42 16 3 H 0.07 0.97 8.14 -51.93 -0.42 0.55 16 4 C -0.11 -1.01 6.17 -24.90 -0.15 -1.17 16 5 C 0.08 0.66 3.34 -65.56 -0.22 0.45 16 6 H 0.09 0.86 7.87 -51.93 -0.41 0.45 16 7 N -0.67 -5.08 6.39 -104.46 -0.67 -5.75 16 8 C 0.06 0.42 5.03 -3.82 -0.02 0.40 16 9 C -0.08 -0.54 2.40 -90.62 -0.22 -0.76 16 10 C -0.12 -0.76 4.98 -26.73 -0.13 -0.89 16 11 C -0.12 -0.72 5.92 -26.73 -0.16 -0.88 16 12 C -0.12 -0.72 5.92 -26.73 -0.16 -0.88 16 13 C -0.12 -0.69 5.92 -26.75 -0.16 -0.85 16 14 C -0.11 -0.71 5.20 -26.76 -0.14 -0.85 16 15 C 0.08 0.83 6.30 -2.53 -0.02 0.82 16 16 N -0.62 -9.08 3.06 -163.02 -0.50 -9.58 16 17 C 0.55 10.76 7.66 -10.99 -0.08 10.67 16 18 O -0.51 -11.92 14.91 5.55 0.08 -11.83 16 19 C -0.15 -3.07 5.16 36.01 0.19 -2.88 16 20 S -0.06 -1.65 20.57 -107.50 -2.21 -3.86 16 21 C -0.53 -15.32 9.50 30.94 0.29 -15.03 16 22 H 0.07 1.97 7.80 -52.48 -0.41 1.56 16 23 C 0.07 2.10 5.49 -17.43 -0.10 2.00 16 24 N -0.87 -26.25 13.22 55.49 0.73 -25.52 16 25 Si 0.92 21.47 29.55 -169.99 -5.02 16.45 16 26 H -0.27 -6.15 7.11 56.52 0.40 -5.75 16 27 H -0.28 -6.42 7.11 56.52 0.40 -6.02 16 28 H -0.28 -6.42 7.11 56.52 0.40 -6.02 16 29 H 0.05 0.66 8.14 -51.92 -0.42 0.24 16 30 H 0.07 1.14 6.91 -51.93 -0.36 0.79 16 31 H 0.06 0.62 8.14 -51.93 -0.42 0.20 16 32 H 0.08 0.65 8.14 -51.93 -0.42 0.23 16 33 H 0.08 0.69 7.86 -51.93 -0.41 0.28 16 34 H 0.34 2.45 6.50 -39.29 -0.26 2.19 16 35 H 0.07 0.54 8.09 -51.93 -0.42 0.12 16 36 H 0.03 0.27 8.14 -51.93 -0.42 -0.16 16 37 H 0.08 0.56 8.14 -51.93 -0.42 0.14 16 38 H 0.06 0.44 8.14 -51.93 -0.42 0.01 16 39 H 0.06 0.40 6.68 -51.93 -0.35 0.05 16 40 H 0.06 0.37 8.14 -51.92 -0.42 -0.05 16 41 H 0.06 0.36 8.14 -51.93 -0.42 -0.06 16 42 H 0.06 0.33 8.14 -51.93 -0.42 -0.10 16 43 H 0.06 0.39 8.14 -51.93 -0.42 -0.03 16 44 H 0.06 0.35 8.14 -51.93 -0.42 -0.07 16 45 H 0.06 0.33 8.14 -51.93 -0.42 -0.09 16 46 H 0.06 0.37 8.14 -51.93 -0.42 -0.05 16 47 H 0.06 0.42 8.14 -51.93 -0.42 -0.01 16 48 H 0.07 0.68 7.77 -51.93 -0.40 0.27 16 49 H 0.08 0.85 7.47 -51.93 -0.39 0.47 16 50 H 0.09 1.70 8.14 -51.92 -0.42 1.28 16 51 H 0.09 1.69 7.84 -51.92 -0.41 1.28 16 52 H 0.27 7.51 8.31 -40.82 -0.34 7.17 16 LS Contribution 413.97 15.07 6.24 6.24 Total: -1.00 -33.05 413.97 -12.02 -45.07 By element: Atomic # 1 Polarization: 8.58 SS G_CDS: -9.71 Total: -1.13 kcal Atomic # 6 Polarization: -9.13 SS G_CDS: -0.97 Total: -10.09 kcal Atomic # 7 Polarization: -40.41 SS G_CDS: -0.43 Total: -40.84 kcal Atomic # 8 Polarization: -11.92 SS G_CDS: 0.08 Total: -11.83 kcal Atomic # 14 Polarization: 21.47 SS G_CDS: -5.02 Total: 16.45 kcal Atomic # 16 Polarization: -1.65 SS G_CDS: -2.21 Total: -3.86 kcal Total LS contribution 6.24 Total: 6.24 kcal Total: -33.05 -12.02 -45.07 kcal The number of atoms in the molecule is 52 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. ZINC001676710816.mol2 52 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 -19.875 kcal (2) G-P(sol) polarization free energy of solvation -33.052 kcal (3) G-ENP(sol) elect.-nuc.-pol. free energy of system -52.927 kcal (4) G-CDS(sol) cavity-dispersion-solvent structure free energy -12.019 kcal (5) G-P-CDS(sol) = G-P(sol) + G-CDS(sol) = (2) + (4) -45.071 kcal (6) G-S(sol) free energy of system = (1) + (5) -64.946 kcal 1SCF WAS SPECIFIED, SO GEOMETRY OPTIMIZATION WAS NOT USED Total computer time = 1.81 seconds