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[求助]
关于Dmol3计算热力学参数的问题,与实验值差距很大
如题,我尝试计算了H2S的热力学参数,输出文件中结果如下。
T Entropy Heat_Capacity Enthalpy Free_Energy
(K) S (cal/mol.K) Cp H (kcal/mol) G
(ZPVE is included)
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1 25.00 0.000 0.000 9.437 9.437
2 50.00 0.000 0.000 9.437 9.437
3 75.00 0.000 0.000 9.437 9.437
4 100.00 0.000 0.000 9.437 9.437
5 125.00 0.000 0.000 9.437 9.437
6 150.00 0.000 0.003 9.437 9.437
7 175.00 0.001 0.011 9.437 9.437
8 200.00 0.004 0.028 9.437 9.437
9 225.00 0.009 0.058 9.438 9.436
10 250.00 0.017 0.100 9.440 9.436
11 275.00 0.029 0.155 9.443 9.436
12 298.15 0.044 0.214 9.448 9.435
13 300.00 0.045 0.219 9.448 9.435
14 325.00 0.065 0.292 9.455 9.433
15 350.00 0.090 0.371 9.463 9.431
16 375.00 0.118 0.455 9.473 9.429
17 400.00 0.150 0.542 9.486 9.425
18 425.00 0.186 0.632 9.500 9.421
19 450.00 0.225 0.724 9.517 9.416
20 475.00 0.266 0.818 9.536 9.410
21 500.00 0.311 0.913 9.558 9.403
22 525.00 0.358 1.010 9.582 9.394
23 550.00 0.407 1.108 9.609 9.385
24 575.00 0.458 1.207 9.638 9.374
25 600.00 0.512 1.307 9.669 9.362
26 625.00 0.567 1.408 9.703 9.348
27 650.00 0.624 1.509 9.739 9.334
28 675.00 0.683 1.611 9.778 9.317
29 700.00 0.744 1.712 9.820 9.299
30 725.00 0.806 1.813 9.864 9.280
31 750.00 0.869 1.914 9.911 9.259
32 775.00 0.933 2.014 9.960 9.237
33 800.00 0.999 2.112 10.011 9.212
34 825.00 1.065 2.210 10.065 9.187
35 850.00 1.133 2.306 10.122 9.159
36 875.00 1.201 2.401 10.181 9.130
37 900.00 1.270 2.493 10.242 9.099
38 925.00 1.339 2.584 10.305 9.066
39 950.00 1.409 2.673 10.371 9.032
40 975.00 1.480 2.760 10.439 8.996
41 1000.00 1.551 2.845 10.509 8.958
这个结果跟查到的H2S 热力学参数差距非常大,
J·K-1 mol-1
T/K Cp° S° -[G°-H°(Tr)]/T H-H°(Tr) fH° fG° log Kf
0 0. 0. INFINITE -9.962 -17.584 -17.584 INFINITE
100 33.259 168.972 235.330 -6.636 -17.947 -23.519 12.285
200 33.380 192.038 208.586 -3.310 -18.957 -28.754 7.510
298.15 34.192 205.757 205.757 0. -20.502 -33.329 5.839
300 34.208 205.969 205.758 0.063 -20.534 -33.408 5.817
400 35.581 215.992 207.115 3.551 -24.549 -37.343 4.876
500 37.192 224.102 209.726 7.188 -27.762 -40.179 4.197
600 38.936 231.037 212.713 10.994 -30.470 -42.399 3.691
700 40.740 237.174 215.777 14.978 -32.771 -44.201 3.298
800 42.518 242.731 218.804 19.142 -34.771 -45.694 2.984
900 44.212 247.838 221.750 23.479 -89.665 -45.870 2.662
1000 45.786 252.579 224.599 27.980 -90.024 -40.984 2.141
而文献中计算得到的参数又跟实验值吻合的很好,参数设置我也是根据那篇文献来的,但结果怎么会这样。。。。求大侠指点
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