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标题: 求助高聚物极性应该如何分析呢？ [打印本页]

作者
Author: scu406 时间: 2022-10-21 12:35
标题: 求助高聚物极性应该如何分析呢？
各位老师好，我想分析聚氨酯、聚丙烯酸酯、聚硅氧烷的极性，例如聚丙烯酸、聚己二酸丁二醇酯、聚甲基硅油，应该如何分析呢？

作者
Author: 兰兰爱学习 时间: 2022-10-21 14:14
可以做一个静电势分析吧

作者
Author: sobereva 时间: 2022-10-21 19:09
谈谈如何衡量分子的极性
http://sobereva.com/518（http://bbs.keinsci.com/thread-14971-1-1.html）

作者
Author: scu406 时间: 2022-10-28 20:19

sobereva 发表于 2022-10-21 19:09
谈谈如何衡量分子的极性
http://sobereva.com/518（http://bbs.keinsci.com/thread-14971-1-1.html）

sobereva老师，您好。按照你的518，输入程序步骤12和0分析后，出现了这样的界面：

---------- Post-processing menu ----------
-3 Visualize the surface
-2 Export the grid data to surf.cub in current folder
-1 Return to upper level menu
0 View molecular structure, surface minima and maxima
1 Export surface extrema as surfanalysis.txt in current folder
2 Export surface extrema as surfanalysis.pdb in current folder
3 Discard surface minima in certain value range
4 Discard surface maxima in certain value range
5 Export molecule as pdb format file
6 Export all surface vertices to vtx.pdb in current folder
7 Export all surface vertices to vtx.txt in current folder
8 Export all surface vertices and surface extrema as vtx.pqr and extrema.pqr
9 Output surface area in specific value range of mapped function
10 Output the closest and farthest distance between the surface and a point
11 Output surface properties of each atom
12 Output surface properties of specific fragment
13 Calculate grid data of mapped function and export it to mapfunc.cub
14 Calculate area and function average in a region around a surface extreme
15 Basin-like partition of surface and calculate areas
18 Discard some surface extrema by inputting their indices
19 Merge some surface extrema and take their average position

并不是一堆数据，是不是我哪里有问题呢？

作者
Author: sobereva 时间: 2022-10-29 04:34

scu406 发表于 2022-10-28 20:19
sobereva老师，您好。按照你的518，输入程序步骤12和0分析后，出现了这样的界面：

...

把屏幕上的信息看完整，往上拉滚动条

作者
Author: scu406 时间: 2022-10-29 08:06
谢谢，找到了，谢谢sbereva老师

作者
Author: scu406 时间: 2022-10-29 08:06
谢谢sobereva老师

作者
Author: scu406 时间: 2022-10-29 12:02

sobereva 发表于 2022-10-29 04:34
把屏幕上的信息看完整，往上拉滚动条

sobereva老师，你好。你的文章写的是ethylamine.fch  //用B3LYP/def2-SVP优化，之后B3LYP/def2-TZVP算单点产生的文件，我用Gview生成gjf文件，然后用文件编辑修改成#p b3lyp/def2TZVP,然后用Gaussion打开gif文件，运行后用utilities输出成fch文件，然后用multiwfn处理。得到的结果如下：和你的数据不一致，我应该怎么处理呢？

   ================= Summary of surface analysis =================

Volume: 564.74812 Bohr^3  (  83.68704 Angstrom^3)
Estimated density according to mass and volume (M/V): 0.8946 g/cm^3
Minimal value: -35.96406 kcal/mol Maximal value:    25.02805 kcal/mol
Overall surface area:       359.42225 Bohr^2  ( 100.64848 Angstrom^2)
Positive surface area:       235.45799 Bohr^2  (  65.93495 Angstrom^2)
Negative surface area:       123.96426 Bohr^2  (  34.71353 Angstrom^2)
Overall average value: 0.00227507 a.u. (    1.42763 kcal/mol)
Positive average value: 0.01221851 a.u. (    7.66723 kcal/mol)
Negative average value:  -0.01661152 a.u. ( -10.42389 kcal/mol)
Overall variance (sigma^2_tot):  0.00037810 a.u.^2 ( 148.88248 (kcal/mol)^2)
Positive variance:       0.00010627 a.u.^2 (    41.84628 (kcal/mol)^2)
Negative variance:       0.00027182 a.u.^2 ( 107.03619 (kcal/mol)^2)
Balance of charges (nu): 0.20206931
Product of sigma^2_tot and nu: 0.00007640 a.u.^2 ( 30.08458 (kcal/mol)^2)
Internal charge separation (Pi): 0.01317928 a.u. (    8.27013 kcal/mol)
Molecular polarity index (MPI): 0.37371160 eV (    8.61800 kcal/mol)
Nonpolar surface area (|ESP| <= 10 kcal/mol):    68.66 Angstrom^2  ( 68.22 %)
Polar surface area (|ESP| > 10 kcal/mol):       31.98 Angstrom^2  ( 31.78 %)

Surface analysis finished!
Total wall clock time passed during this task:    2 s
Note: Previous orbital information has been restored
Citation of molecular polarity index (MPI): Carbon, 171, 514 (2021) DOI: 10.1016/j.carbon.2020.09.048

作者
Author: sobereva 时间: 2022-10-30 05:51

scu406 发表于 2022-10-29 12:02
sobereva老师，你好。你的文章写的是ethylamine.fch //用B3LYP/def2-SVP优化，之后B3LYP/def2-TZVP算单 ...

记住Gaussian怎么拼
分清楚gif和gjf

没细节没法说，gjf、输出文件、fch文件你也不提供，用的几何结构是否一样、关键词是否正确、Gaussian版本是否一样都没法确定。所有可能影响结果的因素都要自觉主动交代清楚

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