Wall clock time and date at job start Sat Mar 6 2021 15:56:39 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= 0 * AM1 - THE AM1 HAMILTONIAN TO BE USED * SM5.42R - SM5.42R CALCULATIONS WILL BE PERFORMED * - CHARGE MODEL 2 WILL BE USED (CM2A) * - THE SOLVENT IS WATER ******************************************************************************* 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 1.42898 * 1 3 3 C 1.35710 * 117.00104 * 2 1 4 4 C 1.38686 * 119.86395 * 359.97438 * 3 2 1 5 5 C 1.38445 * 120.03402 * 180.02562 * 4 3 2 6 6 O 1.35655 * 120.12025 * 179.70903 * 5 4 3 7 7 C 1.42896 * 116.99982 * 359.97438 * 6 5 4 8 8 C 1.40295 * 119.75966 * 359.97438 * 5 4 3 9 9 C 1.47296 * 120.13726 * 179.97438 * 8 5 4 10 10 O 1.21618 * 120.00249 * 0.02562 * 9 8 5 11 11 N 1.34777 * 120.00110 * 179.97438 * 9 8 5 12 12 C 1.46505 * 119.99893 * 180.02562 * 11 9 8 13 13 C 1.50699 * 109.46848 * 180.02562 * 12 11 9 14 14 C 1.38236 * 120.00110 * 269.72641 * 13 12 11 15 15 C 1.38234 * 120.00215 * 179.76990 * 14 13 12 16 16 C 1.38237 * 119.99832 * 0.50254 * 15 14 13 17 17 Si 1.86802 * 119.99906 * 179.72595 * 16 15 14 18 18 C 1.86298 * 109.46956 * 270.02423 * 17 16 15 19 19 C 1.86299 * 109.47048 * 30.02205 * 17 16 15 20 20 C 1.86294 * 109.46924 * 150.02419 * 17 16 15 21 21 C 1.38238 * 119.99902 * 359.75180 * 16 15 14 22 22 C 1.38234 * 120.00072 * 359.97438 * 21 16 15 23 23 C 1.39860 * 119.72811 * 0.02562 * 8 5 4 24 24 C 1.37543 * 119.96343 * 0.02562 * 23 8 5 25 25 C 1.50705 * 119.87660 * 179.97438 * 24 23 8 26 26 O 1.42902 * 109.46953 * 254.97555 * 25 24 23 27 27 Si 1.86297 * 109.47138 * 14.97847 * 25 24 23 28 28 H 1.48501 * 109.47278 * 60.00064 * 27 25 24 29 29 H 1.48497 * 109.47007 * 180.02562 * 27 25 24 30 30 H 1.48505 * 109.47181 * 299.99920 * 27 25 24 31 31 H 1.08999 * 109.47574 * 179.97438 * 1 2 3 32 32 H 1.09004 * 109.47529 * 300.01121 * 1 2 3 33 33 H 1.09007 * 109.46673 * 60.00708 * 1 2 3 34 34 H 1.07998 * 119.98344 * 359.97438 * 4 3 2 35 35 H 1.09000 * 109.47375 * 300.00279 * 7 6 5 36 36 H 1.08999 * 109.47412 * 60.00593 * 7 6 5 37 37 H 1.09003 * 109.47105 * 180.02562 * 7 6 5 38 38 H 0.96998 * 120.00300 * 0.02562 * 11 9 8 39 39 H 1.08998 * 109.47258 * 299.99721 * 12 11 9 40 40 H 1.09001 * 109.47184 * 60.00311 * 12 11 9 41 41 H 1.08000 * 119.99738 * 359.97438 * 14 13 12 42 42 H 1.08004 * 119.99733 * 180.22977 * 15 14 13 43 43 H 1.09001 * 109.47516 * 60.00298 * 18 17 16 44 44 H 1.09002 * 109.47340 * 179.97438 * 18 17 16 45 45 H 1.09003 * 109.47228 * 299.99875 * 18 17 16 46 46 H 1.09005 * 109.46962 * 59.99914 * 19 17 16 47 47 H 1.08998 * 109.47113 * 179.97438 * 19 17 16 48 48 H 1.09001 * 109.47384 * 299.99677 * 19 17 16 49 49 H 1.09003 * 109.47267 * 60.00120 * 20 17 16 50 50 H 1.08998 * 109.46969 * 180.02562 * 20 17 16 51 51 H 1.09005 * 109.47314 * 299.99582 * 20 17 16 52 52 H 1.07995 * 119.99515 * 179.97438 * 21 16 15 53 53 H 1.07998 * 120.00048 * 179.97438 * 22 21 16 54 54 H 1.08000 * 120.01681 * 179.97438 * 23 8 5 55 55 H 1.08997 * 109.46774 * 134.97631 * 25 24 23 56 56 H 0.96702 * 113.99992 * 60.00352 * 26 25 24 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 2.0451 1.2092 0.0000 4 6 1.2870 2.3705 -0.0005 5 6 1.9119 3.6059 -0.0011 6 8 1.1721 4.7430 -0.0076 7 6 -0.2489 4.5924 -0.0142 8 6 3.3130 3.6776 -0.0005 9 6 3.9865 4.9876 -0.0017 10 8 3.3279 6.0100 -0.0026 11 7 5.3327 5.0532 -0.0006 12 6 6.0025 6.3562 -0.0012 13 6 7.4958 6.1533 -0.0004 14 6 8.1810 6.0667 1.1971 15 6 9.5500 5.8758 1.1978 16 6 10.2355 5.7819 0.0010 17 14 12.0866 5.5316 0.0020 18 6 12.9373 7.1891 0.0014 19 6 12.5837 4.5791 1.5240 20 6 12.5850 4.5772 -1.5183 21 6 9.5510 5.8738 -1.1965 22 6 8.1811 6.0590 -1.1972 23 6 4.0677 2.5001 0.0000 24 6 3.4352 1.2787 -0.0005 25 6 4.2503 0.0111 -0.0005 26 8 4.2147 -0.5781 -1.3019 27 14 6.0132 0.4065 0.4542 28 1 6.0502 1.0187 1.8066 29 1 6.8165 -0.8425 0.4536 30 1 6.5782 1.3583 -0.5358 31 1 -0.3634 -1.0276 -0.0005 32 1 -0.3634 0.5140 0.8899 33 1 -0.3633 0.5138 -0.8901 34 1 0.2087 2.3111 -0.0014 35 1 -0.5517 4.0409 -0.9043 36 1 -0.5605 4.0454 0.8757 37 1 -0.7185 5.5760 -0.0194 38 1 5.8581 4.2378 0.0005 39 1 5.7124 6.9135 -0.8919 40 1 5.7110 6.9150 0.8881 41 1 7.6461 6.1448 2.1321 42 1 10.0848 5.8044 2.1335 43 1 12.6458 7.7475 0.8909 44 1 14.0175 7.0431 0.0024 45 1 12.6465 7.7464 -0.8891 46 1 12.0859 3.6094 1.5244 47 1 13.6638 4.4327 1.5244 48 1 12.2921 5.1376 2.4135 49 1 12.2942 5.1345 -2.4088 50 1 13.6651 4.4307 -1.5175 51 1 12.0873 3.6074 -1.5179 52 1 10.0866 5.8009 -2.1315 53 1 7.6465 6.1312 -2.1328 54 1 5.1466 2.5498 0.0000 55 1 3.8356 -0.6874 0.7261 56 1 4.5692 -0.0109 -2.0003 RHF calculation, no. of doubly occupied orbitals= 73 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=0 AM1 1SCF TLIMIT=15 GEO-OK SM5.42R & SOLVNT=WATER s_22_10854838_12297780.mol2 56 1SCF WAS SPECIFIED, SO GEOMETRY OPTIMIZATION WAS NOT USED SCF FIELD WAS ACHIEVED Wall clock time and date at job start Sat Mar 6 2021 15:56:39 Heat of formation + Delta-G solvation = -124.720873 kcal Electronic energy + Delta-G solvation = -35960.966623 eV Core-core repulsion = 31345.578743 eV Total energy + Delta-G solvation = -4615.387880 eV No. of doubly occupied orbitals = 73 Molecular weight (most abundant/longest-lived isotopes) = 403.182 amu Computer time = 1.81 seconds Orbital eigenvalues (eV) -42.13469 -40.78159 -40.11922 -39.65331 -38.47382 -37.00004 -36.00211 -32.77036 -32.26117 -31.86059 -31.38917 -29.41316 -28.99057 -28.28349 -28.27751 -28.25669 -26.96561 -26.10319 -24.45223 -23.44797 -22.83949 -22.03182 -21.58263 -20.13749 -18.97690 -18.40159 -17.99610 -17.33489 -17.24276 -17.08925 -16.68862 -16.55998 -16.47862 -16.25918 -15.86166 -15.80910 -15.66768 -15.58943 -15.37311 -14.92666 -14.52334 -14.32909 -14.15979 -14.06300 -13.99612 -13.89442 -13.87797 -13.69234 -13.44386 -13.42095 -13.29996 -13.13264 -13.09706 -12.95378 -12.67162 -12.64802 -12.53965 -12.53293 -12.24366 -12.11990 -11.91799 -11.79072 -11.66992 -11.12888 -10.87118 -10.75440 -10.74373 -10.37879 -10.27042 -9.95055 -9.79365 -9.65466 -9.22109 -0.30989 0.04246 0.19294 0.53267 1.14066 1.38511 1.49893 1.68817 1.85409 1.90325 1.99170 2.04211 2.10001 2.15093 2.23811 2.55644 2.67943 2.97783 3.39308 3.49145 3.57750 3.69637 3.72711 3.82414 3.91462 4.08345 4.13033 4.16832 4.21944 4.27044 4.28493 4.31810 4.35573 4.52586 4.55849 4.61631 4.65466 4.69646 4.71856 4.75814 4.85320 4.85518 4.89657 4.89754 4.91079 4.91396 4.91840 5.00075 5.01939 5.18846 5.24325 5.28281 5.41683 5.59566 5.60418 5.63459 5.68747 5.72755 6.02299 6.13648 6.26553 6.42248 6.75761 7.13378 Net atomic charges, atomic populations, and dipole contributions calculated with CM2 Atom NO. Type Charge No. of electrons 1 C 0.011 3.989 2 O -0.308 6.308 3 C 0.220 3.780 4 C -0.309 4.309 5 C 0.220 3.780 6 O -0.305 6.305 7 C 0.010 3.990 8 C -0.228 4.228 9 C 0.563 3.437 10 O -0.562 6.562 11 N -0.718 5.718 12 C 0.166 3.834 13 C -0.109 4.109 14 C -0.124 4.124 15 C -0.100 4.100 16 C -0.373 4.373 17 Si 1.127 2.873 18 C -0.465 4.465 19 C -0.462 4.462 20 C -0.462 4.462 21 C -0.099 4.099 22 C -0.123 4.123 23 C -0.010 4.010 24 C -0.201 4.201 25 C -0.063 4.063 26 O -0.549 6.549 27 Si 0.956 3.044 28 H -0.250 1.250 29 H -0.265 1.265 30 H -0.233 1.233 31 H 0.121 0.879 32 H 0.070 0.930 33 H 0.068 0.932 34 H 0.166 0.834 35 H 0.072 0.928 36 H 0.072 0.928 37 H 0.113 0.887 38 H 0.406 0.594 39 H 0.070 0.930 40 H 0.070 0.930 41 H 0.126 0.874 42 H 0.139 0.861 43 H 0.066 0.934 44 H 0.073 0.927 45 H 0.066 0.934 46 H 0.070 0.930 47 H 0.073 0.927 48 H 0.071 0.929 49 H 0.072 0.928 50 H 0.073 0.927 51 H 0.070 0.930 52 H 0.139 0.861 53 H 0.126 0.874 54 H 0.151 0.849 55 H 0.116 0.884 56 H 0.386 0.614 For the charges calculated by CM2: Dipole moment (debyes) X Y Z Total from point charges 1.267 -3.355 0.042 3.587 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 -0.083 4.083 2 O -0.219 6.219 3 C 0.172 3.828 4 C -0.328 4.328 5 C 0.170 3.830 6 O -0.215 6.215 7 C -0.084 4.084 8 C -0.233 4.233 9 C 0.352 3.648 10 O -0.442 6.442 11 N -0.371 5.371 12 C 0.043 3.957 13 C -0.110 4.110 14 C -0.142 4.142 15 C -0.118 4.118 16 C -0.413 4.413 17 Si 1.314 2.686 18 C -0.571 4.571 19 C -0.570 4.570 20 C -0.569 4.569 21 C -0.117 4.117 22 C -0.141 4.141 23 C -0.028 4.028 24 C -0.202 4.202 25 C -0.173 4.173 26 O -0.356 6.356 27 Si 0.778 3.222 28 H -0.173 1.173 29 H -0.190 1.190 30 H -0.157 1.157 31 H 0.139 0.861 32 H 0.089 0.911 33 H 0.087 0.913 34 H 0.184 0.816 35 H 0.091 0.909 36 H 0.091 0.909 37 H 0.131 0.869 38 H 0.243 0.757 39 H 0.089 0.911 40 H 0.088 0.912 41 H 0.144 0.856 42 H 0.157 0.843 43 H 0.085 0.915 44 H 0.092 0.908 45 H 0.085 0.915 46 H 0.089 0.911 47 H 0.092 0.908 48 H 0.090 0.910 49 H 0.091 0.909 50 H 0.092 0.908 51 H 0.089 0.911 52 H 0.157 0.843 53 H 0.144 0.856 54 H 0.168 0.832 55 H 0.134 0.866 56 H 0.235 0.765 Dipole moment (debyes) X Y Z Total from point charges 1.417 -2.869 0.590 3.254 hybrid contribution -1.006 0.270 -0.345 1.097 sum 0.411 -2.599 0.246 2.643 Atomic orbital electron populations 1.23492 0.76055 1.06128 1.02635 1.86151 1.23629 1.25845 1.86318 1.18852 0.91487 0.84227 0.88226 1.21444 1.02216 0.90524 1.18646 1.18938 0.90047 0.85668 0.88323 1.86364 1.20827 1.28356 1.85995 1.23490 0.76549 1.05660 1.02750 1.19086 0.91081 0.93434 1.19650 1.18095 0.82145 0.88632 0.75912 1.90817 1.65488 1.36919 1.50951 1.45902 1.05607 1.09814 1.75771 1.20141 0.88027 0.84814 1.02687 1.19822 0.93919 1.02854 0.94360 1.21367 0.95478 0.99914 0.97471 1.21386 0.93761 0.97390 0.99225 1.27995 1.18493 1.00935 0.93869 0.77160 0.59622 0.65661 0.66158 1.26323 1.08169 1.18306 1.04333 1.26280 1.05956 1.08995 1.15726 1.26275 1.05958 1.09008 1.15678 1.21386 0.93763 0.97353 0.99203 1.21363 0.95446 0.99847 0.97460 1.20944 0.99752 0.89624 0.92499 1.19569 0.91679 0.96052 1.12916 1.24813 1.09085 0.94035 0.89341 1.86524 1.86974 1.45403 1.16668 0.85646 0.74479 0.80545 0.81481 1.17349 1.18984 1.15652 0.86117 0.91102 0.91337 0.81646 0.90942 0.90895 0.86874 0.75720 0.91132 0.91180 0.85617 0.84338 0.91505 0.90775 0.91480 0.91128 0.90755 0.90958 0.90929 0.90760 0.91119 0.84301 0.85556 0.83215 0.86624 0.76500 Number of geometries 1 Number of calculations of the screened coulomb radii 1 The total number of SCF iterations 15. 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 0.01 -0.06 9.80 113.37 1.11 1.05 16 2 O -0.31 -0.62 9.80 -90.31 -0.88 -1.51 16 3 C 0.22 0.65 6.67 22.60 0.15 0.80 16 4 C -0.31 -0.69 8.01 22.43 0.18 -0.51 16 5 C 0.22 1.59 6.70 22.82 0.15 1.74 16 6 O -0.30 -2.82 8.56 -68.74 -0.59 -3.41 16 7 C 0.01 -0.01 9.81 113.37 1.11 1.10 16 8 C -0.23 -1.66 5.89 -20.00 -0.12 -1.78 16 9 C 0.56 5.94 7.76 86.63 0.67 6.61 16 10 O -0.56 -10.37 15.15 16.88 0.26 -10.11 16 11 N -0.72 -3.30 5.50 -470.22 -2.59 -5.89 16 12 C 0.17 0.74 5.80 85.63 0.50 1.23 16 13 C -0.11 -0.24 5.25 -19.87 -0.10 -0.34 16 14 C -0.12 -0.15 9.70 22.27 0.22 0.06 16 15 C -0.10 0.08 9.29 22.27 0.21 0.29 16 16 C -0.37 0.75 4.59 22.27 0.10 0.85 16 17 Si 1.13 -7.41 12.32 68.60 0.85 -6.57 16 18 C -0.47 1.76 8.65 113.37 0.98 2.74 16 19 C -0.46 2.40 8.53 113.37 0.97 3.36 16 20 C -0.46 2.43 8.53 113.37 0.97 3.40 16 21 C -0.10 0.09 9.29 22.27 0.21 0.30 16 22 C -0.12 -0.13 9.70 22.27 0.22 0.09 16 23 C -0.01 -0.02 8.14 22.50 0.18 0.16 16 24 C -0.20 -0.42 5.27 -19.80 -0.10 -0.53 16 25 C -0.06 -0.01 2.37 71.24 0.17 0.15 16 26 O -0.55 -0.78 12.88 -148.98 -1.92 -2.70 16 27 Si 0.96 -1.72 25.48 68.60 1.75 0.02 16 28 H -0.25 0.22 7.11 99.48 0.71 0.92 16 29 H -0.27 -0.37 7.11 99.48 0.71 0.33 16 30 H -0.23 1.04 6.73 99.48 0.67 1.70 16 31 H 0.12 -0.99 8.14 -2.39 -0.02 -1.01 16 32 H 0.07 -0.54 7.65 -2.39 -0.02 -0.56 16 33 H 0.07 -0.48 7.65 -2.38 -0.02 -0.50 16 34 H 0.17 -0.53 4.50 -2.91 -0.01 -0.54 16 35 H 0.07 -0.30 7.66 -2.39 -0.02 -0.32 16 36 H 0.07 -0.31 7.66 -2.39 -0.02 -0.33 16 37 H 0.11 -0.30 8.14 -2.39 -0.02 -0.32 16 38 H 0.41 0.04 6.48 -92.71 -0.60 -0.56 16 39 H 0.07 0.41 8.08 -2.39 -0.02 0.39 16 40 H 0.07 0.42 8.08 -2.39 -0.02 0.40 16 41 H 0.13 -0.06 8.06 -2.91 -0.02 -0.08 16 42 H 0.14 -0.65 7.43 -2.91 -0.02 -0.67 16 43 H 0.07 -0.20 7.96 -2.39 -0.02 -0.22 16 44 H 0.07 -0.31 7.96 -2.39 -0.02 -0.33 16 45 H 0.07 -0.20 7.96 -2.39 -0.02 -0.22 16 46 H 0.07 -0.34 7.96 -2.38 -0.02 -0.35 16 47 H 0.07 -0.39 7.96 -2.39 -0.02 -0.41 16 48 H 0.07 -0.39 7.69 -2.39 -0.02 -0.41 16 49 H 0.07 -0.40 7.69 -2.39 -0.02 -0.42 16 50 H 0.07 -0.39 7.96 -2.39 -0.02 -0.41 16 51 H 0.07 -0.34 7.96 -2.38 -0.02 -0.36 16 52 H 0.14 -0.68 7.43 -2.91 -0.02 -0.70 16 53 H 0.13 -0.09 8.06 -2.91 -0.02 -0.11 16 54 H 0.15 -0.35 3.19 -2.91 -0.01 -0.36 16 55 H 0.12 0.04 7.82 -2.39 -0.02 0.02 16 56 H 0.39 -2.12 8.70 -74.06 -0.64 -2.76 16 Total: 0.00 -22.58 456.22 5.02 -17.56 By element: Atomic # 1 Polarization: -8.58 SS G_CDS: 0.39 Total: -8.19 kcal Atomic # 6 Polarization: 13.03 SS G_CDS: 7.76 Total: 20.79 kcal Atomic # 7 Polarization: -3.30 SS G_CDS: -2.59 Total: -5.89 kcal Atomic # 8 Polarization: -14.60 SS G_CDS: -3.14 Total: -17.74 kcal Atomic # 14 Polarization: -9.14 SS G_CDS: 2.59 Total: -6.54 kcal Total: -22.58 5.02 -17.56 kcal The number of atoms in the molecule is 56 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. s_22_10854838_12297780.mol2 56 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 -107.159 kcal (2) G-P(sol) polarization free energy of solvation -22.584 kcal (3) G-ENP(sol) elect.-nuc.-pol. free energy of system -129.744 kcal (4) G-CDS(sol) cavity-dispersion-solvent structure free energy 5.023 kcal (5) G-P-CDS(sol) = G-P(sol) + G-CDS(sol) = (2) + (4) -17.562 kcal (6) G-S(sol) free energy of system = (1) + (5) -124.721 kcal 1SCF WAS SPECIFIED, SO GEOMETRY OPTIMIZATION WAS NOT USED Total computer time = 1.81 seconds