QSPR Analysis of Certain Graph Theocratical Matrices and Their Corresponding Energy
Publicado en línea: 25 abr 2017
Páginas: 131 - 150
Recibido: 09 ene 2017
Aceptado: 25 abr 2017
DOI: https://doi.org/10.21042/AMNS.2017.1.00011
Palabras clave
© 2017 Sunilkumar M. Hosamani, Bhagyashri B. Kulkarni, Ratnamma G. Boli, Vijay M. Gadag, published by Sciendo
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.
The molecular descriptor is the final result of logic and mathematical procedure which transform chemical information encoded within a symbolic representation of a molecule into a useful member or the result of some standardized experiments. Attention is paid to the term “useful” with its double meanings. It means that the number can give more insights into the interpretation of the molecular properties and / or is able to take part in a model for the prediction of some interesting property of the molecules.
The numerical invariants of chemical graphs are increasingly being used for a single number characterization of the corresponding chemical compounds [5]. These invariants are named in the chemical literature as topological indices [1, 2] or graph-theocratical indices [29]. The former term is the more common of the two. Topological indices have found application in various areas of chemistry, physics, mathematics, informatics, biology, etc [29], but their most important use to date is in the non-empirical Quantitative Structure- Property Relationships (QSPR) and Quantitative Structure -Activity Relationships (QSAR) [4, 24, 26, 27].
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Since
The energy of
Since
The vertex Zagreb energy of
Since
The forgotten energy of
Since
The harmonic energy of
Since
The Geometric-Airthmetic energy of
Since
The Degree-Sum energy of
Since
The Laplacian energy of
Since
The Sum-Connectivity energy of
Since
The Vertex Randi
We have used nine Graph Theoretical Matrices viz, vertex-adjacency matrix, vertex Zagreb adjacency Matrix, forgotten adjacency matrix, harmonic matrix, geometric-airthmetic matrix, degree-sum matrix, laplacian matrix, sum-connectivity matrix and vertex Randi
S.No. Alkane bp(° mv( mr( hv(kJ) ct(°C) cp(atm) st(dyne/cm) mp(° 1 Butane -0.500 152.01 37.47 -138.35 2 2-methyl propane -11.730 134.98 36 -159.60 3 Pentane 36.074 115.205 25.2656 26.42 196.62 33.31 16.00 -129.72 4 2-methyl butane 27.852 116.426 25.2923 24.59 187.70 32.9 15.00 -159.90 5 2,2 dimethylpropane 9.503 112.074 25.7243 21.78 160.60 31.57 -16.55 6 Hexane 68.740 130.688 29.9066 31.55 234.70 29.92 18.42 -95.35 7 2-methylpentane 60.271 131.933 29.9459 29.86 224.90 29.95 17.38 -153.67 8 3 -methyalpentane 63.282 129.717 29.8016 30.27 231.20 30.83 18.12 -118.00 9 2,2-methylbutane 49.741 132.744 29.9347 27.69 216.20 30.67 16.30 -99.87 10 2,3 -dimethylbutane 57.988 130.240 29.8104 29.12 227.10 30.99 17.37 -128.54 11 Heptanes 98.427 146.540 34.5504 36.55 267.55 27.01 20.26 -90.61 12 2-methylhexane 90.052 147.656 34.5908 34.80 257.90 27.2 19.29 -118.28 13 3-methylhexane 91.850 145.821 34.4597 35.08 262.40 28.1 19.79 -119.40 14 3-ethylpentane 93.475 143.517 34.2827 35.22 267.60 28.6 20.44 -118.60 15 2,2-dimethylpentane 79.197 148.695 34.6166 32.43 247.70 28.4 18.02 -123.81 16 2,3 -dimethylpentane 89.784 144.153 34.3237 34.24 264.60 29.2 19.96 -119.10 17 2,4-dimethylpentane 80.500 148.949 34.6192 32.88 247.10 27.4 18.15 -119.24 18 3,3-dimethylpentane 86.064 144.530 34.3323 33.02 263.00 30 19.59 -134.46 19 Octane 125.665 162.592 39.1922 41.48 296.20 24.64 21.76 -56.79 20 2-methylheptane 117.647 163.663 39.2316 39.68 288.00 24.8 20.60 -109.04 21 3-methylheptane 118.925 161.832 39.1001 39.83 292.00 25.6 21.17 -120.50 22 4-methylheptane 117.709 162.105 39.1174 39.67 290.00 25.6 21.00 -120.95 23 3-ethylhexane 118.53 160.07 38.94 39.40 292.00 25.74 21.51 24 2,2-dimethylhexane 10.84 164.28 39.25 37.29 279.00 25.6 19.60 -121.18 25 2,3-dimethylhexane 115.607 160.39 38.98 38.79 293.00 26.6 20.99 26 2,4-dimethylhexane 109.42 163.09 39.13 37.76 282.00 25.8 20.05 -137.50 27 2,5-dimethylhexane 109.10 164.69 39.25 37.86 279.00 25 19.73 -91.20 28 3,3-dimethy lhexane 111.96 160.87 39.00 37.93 290.84 27.2 20.63 -126.10 29 3,4-dimethy lhexane 117.72 158.81 38.84 39.02 298.00 27.4 21.64 30 3 -ethyl-2-methylpentane 115.65 158.79 38.83 38.52 295.00 27.4 21.52 -114.96 31 3 -ethyl-3 -methylpentane 118.25 157.02 38.71 37.99 305.00 28.9 21.99 -90.87 32 2,2,3-trimethylpentane 109.84 159.52 38.92 36.91 294.00 28.2 20.67 -112.27 33 2,2,4-trimethylpentane 99.23 165.08 39.26 35.13 271.15 25.5 18.77 -107.38 34 2,3,3-trimethylpentane 114.76 157.29 38.76 37.22 303.00 29 21.56 -100.70 35 2,3,4-trimethylpentane 113.46 158.85 38.86 37.61 295.00 27.6 21.14 -109.21 36 2,2, 3,3-tetramethylbutane 106.470 270.8 24.5 36 Nonane 150.79 178.71 43.84 46.44 322.00 22.74 22.92 -53.52 37 2-methyloctane 143.26 179.77 43.87 44.65 315.00 23.6 21.88 -80.40 38 3-methyloctane 144.18 177.95 43.72 44.75 318.00 23.7 22.34 -107.64 39 4-methyloctane 142.48 178.15 43.76 44.75 318.30 23.06 22.34 -113.20 40 3-ethylheptane 143.00 176.41 43.64 44.81 318.00 23.98 22.81 -114.90 41 4-ethylheptane 141.20 175.68 43.49 44.81 318.30 23.98 22.81 42 2,2-dimethylheptane 132.69 180.50 43.91 42.28 302.00 22.8 20.80 -113.00 43 2,3-dimethylheptane 140.50 176.65 43.63 43.79 315.00 23.79 22.34 -116.00 44 2,4-dimethylheptane 133.50 179.12 43.73 42.87 306.00 22.7 23.30 45 2,5-dimethylheptane 136.00 179.37 43.84 43.87 307.80 22.7 21.30 46 2,6- dimethylheptane 135.21 180.91 43.92 42.82 306.00 23.7 20.83 -102.90 47 3,3- dimethylheptane 137.300 176.897 43.6870 42.66 314.00 24.19 22.01 48 3,4- dimethylheptane 140.600 175.349 43.5473 43.84 322.70 24.77 22.80 49 3,5- dimethylheptane 136.000 177.386 43.6379 42.98 312.30 23.59 21.77 50 4,4- dimethylheptane 135.200 176.897 43.6022 42.66 317.80 24.18 22.01 51 3-ethyl-2-methylhexane 138.000 175.445 43.6550 43.84 322.70 24.77 22.80 52 4-ethyl-2-methylhexane 133.800 177.386 43.6472 42.98 330.30 25.56 21.77 53 3-ethyl-3-methylhexane 140.600 173.077 43.2680 44.04 327.20 25.66 23.22 54 2,2,4- trimethylhexane 126.540 179.220 43.7638 40.57 301.00 23.39 20.51 -120.00 55 2,2,5- trimethylhexane 124.084 181.346 43.9356 40.17 296.60 22.41 20.04 -105.78 56 2,3,3- trimethylhexane 137.680 173.780 43.4347 42.23 326.10 25.56 22.41 -116.80 57 2,3,4- trimethylhexane 139.000 173.498 43.4917 42.93 324.20 25.46 22.80 58 2,3,5- trimethylhexane 131.340 177.656 43.6474 41.42 309.40 23.49 21.27 -127.80 59 3,3,4- trimethylhexane 140.460 172.055 43.3407 42.28 330.60 26.45 23.27 -101.20 60 3,3-diethylpentane 146.168 170.185 43.1134 43.36 342.80 26.94 23.75 -33.11 61 2,2-dimethyl-3-ethylpentane 133.830 174.537 43.4571 42.02 322.60 25.96 22.38 -99.20 62 2,3-dimethyl-3-ethylpentane 142.000 170.093 42.9542 42.55 338.60 26.94 23.87 63 2,4-dimethyl-3-ethylpentane 136.730 173.804 43.4037 42.93 324.20 25.46 22.80 -122.20 64 2,2,3,3-tetramethylpentane 140.274 169.495 43.2147 41.00 334.50 27.04 23.38 -99.0 65 2,2,3,4- tetramethylpentane 133.016 173.557 43.4359 41.00 319.60 25.66 21.98 -121.09 66 2,2,4,4- tetramethylpentane 122.284 178.256 43.8747 38.10 301.60 24.58 20.37 -66.54 67 2,3,3,4- tetramethylpentane 141.551 169.928 43.2016 41.75 334.50 26.85 23.31 -102.12
S.No. Alkane 1 Butane 2.828 10 18 2.844 4.268 18.166 6 2.516 3 2 2-methyl propane 2.828 11.243 30 1.732 3 18.422 6 1.732 2 3 Pentane 4.472 14.001 25.999 3.274 5.286 25.874 8 2.98 3.414 4 2-methyl butane 5.226 16 38 2.86 4.758 26.253 8 2.72 3.154 5 2,2 dimethylpropane 4 20 68 1.6 3.2 26.88 8 1.788 2 6 Hexane 6.988 17.99 34 4.086 6.788 33.698 10 3.768 4.236 7 2-methylpentane 6.064 14.999 46 3.254 5.722 34.168 10 3.15 3.528 8 3 -methyalpentane 6.9 20 46 3.924 6.442 34.168 10 3.652 4.23 9 2,2-methylbutane 5.818 23.992 76.001 2.798 5.024 34.485 10 2.824 3.224 10 2,3 -dimethylbutane 6.004 22 58 2.906 5.292 34.628 10 2.944 3.334 11 Heptanes 8.054 21.999 41.98 4.59 7.868 41.58 12 4.284 4.732 12 2-methylhexane 7.728 24.001 53.991 4.282 7.266 42.12 11.999 4.17 4.376 13 3-methylhexane 7.88 24 54 4.376 7.456 43.058 11.999 4.112 4.632 15 3-ethylpentane 6.9 20 56 4.586 7.654 38.08 10 4.24 4.828 16 2,2-dimethylpentane 6.72 27.999 83.999 3.176 5.966 43.06 12.001 3.24 3.582 17 2,3 -dimethylpentane 7.664 24.999 65.999 3.966 6.92 42.648 12.001 3.872 4.404 18 2,4-dimethylpentane 6.156 20 46 3.226 6.148 43.015 10 3.312 3.632 19 3,3-dimethylpentane 6.596 28 83.999 3.944 6.802 43.266 12 3.666 5.74 20 Octane 9.516 26 50 5.324 9.312 49.496 14 4.76 5.468 21 2-methylheptane 8.764 28 62 4.792 8.294 50.09 14 4.33 4.82 22 3-methylheptane 9.408 27.999 62 5.138 8.924 49.996 14 4.608 5.41 23 4-methylheptane 8.828 27.999 62 4.734 8.402 50.09 14 4.298 4.974 24 3-ethylhexane 7.88 24 54 5.282 9.034 50.09 11.999 4.536 5.502 25 2,2-dimethylhexane 8.312 31.999 91.999 4.008 7.522 51.14 14 3.892 4.424 26 2,3-dimethylhexane 8.646 30.001 73.999 4.376 7.95 50.671 15 4.198 4.792 27 2,4-dimethylhexane 8.564 30 74 4.314 7.862 49.825 14.001 4.114 4.678 28 2,5-dimethylhexane 8.472 30 74 3.714 7.095 50.671 14 3.761 4.468 29 3,3-dimethylhexane 8.52 31.998 92 4.334 7.772 51.14 14 3.968 4.752 30 3,4-dimethylhexane 9.332 30 74 5.002 8.584 50.413 14.001 4.5 5.41 31 3-ethyl-2-methylpentane 7.664 29 70 4.588 4.51 51.016 14 4.16 4.916 32 3-ethyl-3-methylpentane 7.596 32 91.246 5.048 8.526 51.14 14 4.336 5.488 33 2,2,3 -trimethylpentane 7.3 34.001 104 3.902 7.228 51.876 16 3.808 4.448 34 2,2,4-trimethylpentane 7.384 33.999 104 3.1444 6.386 51.701 14 3.056 3.684 35 2,3,3-trimethylpentane 8.054 34 104.001 4.026 7.374 47.686 14 4.068 4.6 36 2,3,4-trimethylpentane 8.424 32 86.001 4.002 7.5 51.24 14 4.09 4.574 36 2,2,3,3-tetramethylbutane 7.212 38 134 2.816 5.892 52.698 15.998 3.179 3.5 37 Nonane 10.628 30 58.001 5.884 10.432 57.432 16 5.574 6.028 38 2-methyloctane 10.252 32 70.001 5.342 9.792 58.07 16 5.22 5.22 39 3-methyloctane 10.472 32 69.998 5.662 10.042 58.07 15.999 5.418 5.954 40 4-methyloctane 10.384 32 70.001 5.58 9.97 58.07 16 5.354 5.858 41 3-ethylheptane 10.564 28.126 69.999 5.864 10.214 58.07 15.999 5.039 5.49 42 4-ethylheptane 10.492 32 70 5.79 10.138 57.842 16 5.3 5.902 43 2,2-dimethylheptane 9.336 35.999 99.999 4.502 8.754 59.21 16 4.355 4.916 44 2,3 -dimethylheptane 10.176 34.001 81.999 5.202 9.49 58.694 16 5.118 5.632 45 2,4-dimethylheptane 9.508 34 81.999 4.728 8.866 58.694 16 4.718 5.132 46 2,5 -dimethylheptane 10.152 34 81.999 5.162 9.438 58.694 16 5.092 5.598 47 2,6- dimethylheptane 10.096 35.999 99.999 4.564 8.536 59.21 15.999 4.64 4.98 48 3,3- dimethylheptane 9.464 33.999 82 5.194 9.324 58.694 16 5.072 5.632 49 3,4- dimethylheptane 10.312 34 81.999 5.45 9.672 59.079 15.999 5.262 3.939 50 3,5- dimethylheptane 10.29 33.999 82.001 5.418 9.628 58.978 16 5.24 5.85 51 4,4- dimethylheptane 9.43 36.001 99.999 4.744 8.73 59.588 16 4.684 5.146 52 3-ethyl-2-methylhexane 10.198 33.999 81.999 5.35 9.606 58.694 16 5.184 5.73 53 4-ethyl-2-methylhexane 10.176 34.001 81.999 5.308 9.55 58.694 15.91 5.158 5.698 54 3-ethyl-3-methylhexane 10.262 36 99.999 5.504 9.56 59.21 15 5.252 5.952 55 2,2,4- trimethylhexane 9.13 38 111.999 4.242 8.134 59.814 15.999 4.372 4.796 56 2,2,5- trimethylhexane 9.06 37.993 112 4.022 8.012 59.814 16 4.256 4.582 57 2,3,3- trimethylhexane 9.3 37.999 112 4.418 8.34 59.814 16.176 4.496 4.97 58 2,3,4- trimethylhexane 10.096 36 93.999 5.068 9.184 59.307 16.001 5.02 5.648 59 2,3,5- trimethylhexane 9.336 36.017 94 4.366 8.428 59.307 15.999 4.5 4.918 60 3,3,4- trimethylhexane 10.036 44 112.002 5.086 9.052 59.814 16 4.994 5.67 61 3,3-diethylpentane 10.472 36 100 5.793 7.736 59.21 15.55 4.903 3.042 62 2,2-dimethyl-3-ethylpentane 9.3 37.999 59.814 4.528 6.954 112.003 16 4.476 4.498 63 2,3-dimethyl-3-ethylpentane 10.062 38.001 61.877 5.116 8.43 112.001 16.001 3.976 4.376 64 2,4-dimethyl-3-ethylpentane 8.884 31 57.368 5.088 8.78 74.999 14 4.818 5.582 65 2,2,3,3-tetramethylpentane 8.98 42 60.9 4.24 7.35 142 15.998 4.122 4.672 66 2,2,3,4- tetramethylpentane 9.02 40 60.408 3.93 7.75 124 16.001 4.168 4.614 67 2,2,4,4- tetramethylpentane 7.936 42 60.9 3.056 6.61 142 16 4.44 3.726 68 2,3,3,4- tetramethylpentane 9.152 39.243 57.278 4.14 7.96 124 14.999 4.992 4.74
We have tested the following linear regression model
where P = physical property, TI = topological index.
Using (3.1), we have obtained the following different linear models for each degree based topological index, which are listed below.
Statical parameters for the linear QSPR model for Boiling point 68 -51.397 19.268 0.959 10.54257 763.634 Molar volume 65 75.5727 10.1894 0.905 7.62675 286.565 Molar refraction 65 13.1325 3.0530 0.912 2.19071 311.823 Heats of vaporization 65 10.0231 3.3206 0.968 1.3755 935.676 Critical temperature 68 91.9103 23.1023 0.936 16.0513 496.344 Critical Pressure 68 28.9043 0.0858 0.006 565.769 0.003 Surface tension 64 11.0052 1.1474 0.871 0.9705 194.411 Melting point 52 -145.3088 4.4911 0.316 25.8886 5.528
Statical parameters for the linear QSPR model for Z1E(G).Boiling point 68 -13.358 4.1092 0.837 20.46726 154.120 Molar volume 65 94.714914 2.201775 0.843 9.6547 155.135 Molar refraction 65 18.6119 0.6778 o.873 2.6070 201.663 Heats of vaporization 65 14.0714 0.7822 0.736 3.7075 74.461 Critical temperature 68 211.4016 1.0167 0.855 23.6776 180.025 Critical Pressure 68 32.606 -0.0988 0.030 119.570 5.061 Surface tension 64 14.4576 0.2108 0.727 1.35607 69.337 Melting point 52 -137.1762 6.6745 0.312 25.9224 5.383
Statical parameters for the linear QSPR model for Boiling point 68 49.581 0.829 0.524 31.8288 25.020 Molar volume 65 127.4698 0.4683 0.551 14.9892 27.500 Molar refraction 65 29.0759 0.1390 0.55 4.4616 27.365 Heats of vaporization 65 490.0581 -5.8696 0.410 4.9948 12.738 Critical temperature 68 131.1926 5.1377 0.525 38.8983 25.158 Critical Pressure 68 31.4563 -0.0249 0.024 135.575 0.038 Surface tension 64 18.4178 0.0341 0.369 1.83471 9.750 Melting point 52 -123.9450 0.2094 0.187 26.7987 1.821
Statical parameters for the linear QSPR model for Boiling point 68 -29.71 32.08 0.825 21.1104 140.91 Molar volume 65 100.054 13.9260 0.682 13.1375 54.809 Molar refraction 65 20.4799 4.2371 0.698 3.8278 59.766 Heats of vaporization 65 31.9676 1.4827 0.856 2.8351 172.070 Critical temperature 67 118.2041 38.4066 0.808 26.9494 123.915 Critical Pressure 68 27.5611 0.4722 0.018 24.6671 0.022 Surface tension 64 12.1028 1.9642 0.804 1.1734 113.396 Melting point 52 -137.1762 6.6745 0.239 26.4944 3.018
Statical parameters for the linear QSPR model for Boiling point 68 -36.99 18.984 0.870 18.4148 205.922 Molar volume 65 90.0410 9.0967 0.791 11.0019 104.98 Molar refraction 65 18.0357 2.6920 0.787 3.2997 102.211 Heats of vaporization 65 34.6289 0.5068 0.89 2.4722 246.160 Critical temperature 68 113.4305 22.2200 0.833 25.3083 149.343 Critical Pressure 68 27.3753 0.2895 0.020 24.661 0.027 Surface tension 64 12.6092 1.0425 0.767 1.2654 88.825 Melting point 52 -132.52 3.28 0.208 26.6869 2.256
Statical parameters for the linear QSPR model for Boiling point 68 59.931 0.897 0.597 29.9848 36.560 Molar volume 65 138.935 0.4028 0.549 15.0099 27.250 Molar refraction 65 31.1877 0.1300 0.596 4.2888 34.79 Heats of vaporization 65 32.5560 0.1074 0.481 4.8027 18.918 Critical temperature 68 219.9439 1.1727 0.638 35.1156 45.347 Critical Pressure 68 32.1358 -0.0444 0.045 81.216 0.133 Surface tension 64 18.4122 0.0436 0.540 1.6617 25.459 Melting point 52 -122.628 0.2430 0.244 26.4571 3.164
Statical parameters for the linear QSPR model for Boiling point 68 105.998 0.795 0.951 11.6074 618.389 Molar volume 65 61.7923 7.1569 0.964 4.7915 822.621 Molar refraction 65 9.2778 2.1462 0.972 1.2624 1065.626 Heats of vaporization 65 28.1626 0.7323 0.924 2.0990 365.873 Critical temperature 68 71.1141 15.5601 0.935 16.1580 462.301 Critical Pressure 68 31.3140 -0.1221 0.014 24.6698 0.012 Surface tension 64 10.9055 0.7551 0.834 1.0888 141.725 Melting point 52 -146.7815 2.8215 0.301 26.0151 4.989
Statical parameters for the linear QSPR model for Boiling point 68 -57.214 39.635 0.907 15.7086 307.683 Molar volume 65 79.5397 19.1531 0.823 10.1925 132.724 Molar refraction 65 14.5174 5.7627 0.833 2.9563 142.822 Heats of vaporization 65 32.3464 1.44459 0.931 1.9928 412.801 Critical temperature 68 86.5805 47.321 0.883 21.4546 233.650 Critical Pressure 68 26.5275 0.7319 0.025 24.6642 0.043 Surface tension 64 0.7399 2.3432 0.847 1.0489 157.493 Melting point 52 -144.7607 8.7341 0.278 26.2084 4.181
Statical parameters for the linear QSPR model for R(G).Boiling point 68 -33.08 30.673 0.776 23.5965 99.608 Molar volume 65 4740.5335 -960.1500 0.655 13.5743 47.350 Molar refraction 65 20.0386 4.0559 0.656 4.0335 47.567 Heats of vaporization 65 24.5656 2.8952 0.764 3.53619 88.107 Critical temperature 68 116.5371 36.2135 0.749 30.3071 84.165 Critical Pressure 68 25.3061 0.9224 0.035 29.00 0.083 Surface tension 64 13.0761 1.6338 0.667 1.46987 49.788 Melting point 52 -113.7685 1.0137 0.035 27.2655 0.061
By inspection of the data in Tables 3 to 11, it is possible to draw a number of conclusions for the given energy like invariants.
First, the famous and much studied invariant, energy of a graph found more suitable tool to predict physical property of alkane, especially Boiling points, Molar volume, Surface tension, Critical temperature, Heats of vaporization and Molar refractions of alkanes with correlation coefficient values
Motivated by vertex Zagreb energy. Here we introduced a new topological invariant namely, vertex Zagreb adjacency energy. The QSPR study of vertex Zagreb energy reveals that Z1E(G) can be useful in predicting the Boiling points, Critical temperatures, Molar volumes and Molar refraction of alkanes also from Table 4,we can see that the correlation coefficient value of
In addition by using the recently advocated idea of using Forgotten index in QSPR studies, we introduced Forgotten adjacency energy. The QSPR study of
The harmonic index did not attract anybody’s attention, especially, not of chemists. No chemical applications of the harmonic index were reported so far, but knowing the present situation in the mathematical chemistry. We here explore the chemical applications of harmonic index. The Table 6 reveals that harmonic energy is also useful tool in predicting the Boiling point, Heats of vaporization, Surface tensions and Critical temperature of alkanes with correlation coefficient values
The QSPR study of Geometric-arithmetic energy reveals that the predicting power of
In addition the results for degree sum energy revealed that the recent advocated idea of using degree sum energy doesn’t pass the test.
The so called Laplacian energy shows remarkably good correlation with the Boiling points, Molar volumes, Molar refractions, Heats of vaporization, Surface tensions and Critical temperatures of alkanes with correlation coefficient values
The sum connectivity energy shows similar correlation properties [ ]. The QSPR study in Table 10 reveals that the predicting power of sum connectivity energy is remarkably good. Infarct the sum connectivity energy can be use as a tool to predict the Heats of vaporization of alkanes. The correlation coefficient value of sum connectivity energy with the Heats of vaporization of alkanes is 0.931. Further the range of correlation coefficient value is 0.025 to 0.931. In fact, the predicting power of sum connectivity energy with Critical pressures of alkanes is almost nil.
The QSPR study of Vertex randic energy does not pass the test.
From practical point of view, topological indices for which the absolute values of correlation coefficient are less than 0.8 can be characterized as useless. Thus the QSPR study of 9 topological indices with physical properties of 68 alkanes helps us to characterize useful topological indices with absolute value of correlation coefficient lies between 0.8 to 0.972.