HW_7_ken
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•Calculate the structures and atomization energies (AE) of XHn (X = H~Ne) by using B3LYP、MP2 theoretical methods with 6-31+G(d,p)、aug-cc-pVTZ then compare with the experimental values.
1. Structures
|
Bond angle ( degree ) |
|
H2 |
LiH |
BeH2 |
BH3 |
CH4 |
NH3 |
H2O |
HF |
|
|
B3LYP/6-31+G(d,p) |
- |
- |
180 |
120 |
109.5 |
108.1 |
105.8 |
- |
|
|
B3LYP/aug-cc-pVTZ |
- |
- |
180 |
120 |
109.5 |
107.2 |
105.1 |
- |
|
|
MP2/6-31+G(d,p) |
- |
- |
180 |
120 |
109.5 |
108.1 |
105.4 |
- |
|
|
MP2/aug-cc-pVTZ |
- |
- |
180 |
120 |
109.5 |
106.8 |
104.1 |
- |
|
|
實驗值 |
- |
- |
180 |
120 |
109.5 |
106.7 |
104.5 |
- |
Reference: Atkins' PHYSICAL CHEMISTRY
|
Bond length (Å) |
|
H2 |
LiH |
BeH2 |
BH3 |
CH4 |
NH3 |
H2O |
HF |
|
|
B3LYP/6-31+G(d,p) |
0.743 |
1.614 |
1.331 |
1.193 |
1.093 |
1.016 |
0.965 |
0.928 |
|
|
B3LYP/aug-cc-pVTZ |
0.743 |
1.59 |
1.325 |
1.188 |
1.088 |
1.013 |
0.962 |
0.924 |
|
|
MP2/6-31+G(d,p) |
0.734 |
1.623 |
1.328 |
1.186 |
1.087 |
1.012 |
0.963 |
0.926 |
|
|
MP2/aug-cc-pVTZ |
0.737 |
1.605 |
1.33 |
1.187 |
1.086 |
1.012 |
0.961 |
0.922 |
|
|
實驗值 |
0.741 |
1.595 |
1.326 |
1.19 |
1.087 |
1.012 |
0.958 |
0.917 |
Reference: Atkins' PHYSICAL CHEMISTRY
| Absolute error of bond length (Å) | H2 | LiH | BeH2 | BH3 | CH4 | NH3 | H2O | HF | MAE | |
| B3LYP/6-31+G(d,p) | 0.002 | 0.019 | 0.005 | 0.003 | 0.006 | 0.004 | 0.007 | 0.011 | 0.007 | |
| B3LYP/aug-cc-pVTZ | 0.002 | 0.005 | 0.001 | 0.002 | 0.001 | 0.001 | 0.004 | 0.007 | 0.003 | |
| MP2/6-31+G(d,p) | 0.007 | 0.028 | 0.002 | 0.004 | 0 | 0 | 0.005 | 0.009 | 0.007 | |
| MP2/aug-cc-pVTZ | 0.004 | 0.01 | 0.004 | 0.003 | 0.001 | 0 | 0.003 | 0.005 | 0.004 |
There is no obvious difference between the two methods, but there are differences in different basic sets
2. Atomization energies
|
Atomization Energy |
|
|
|
|
|
|
|
|
|
unit(kcal/mol) |
H2 |
LiH |
BeH2 |
BH3 |
CH4 |
NH3 |
H2O |
HF |
|
B3LYP/6-31+G(d,p) |
111.7 |
57.0 |
153.7 |
286.7 |
422.8 |
300.1 |
229.5 |
138.2 |
|
B3LYP/aug-cc-pVTZ |
110.1 |
58.4 |
150.7 |
284.7 |
420.6 |
300.6 |
230.5 |
138.8 |
|
MP2/6-31+G(d,p) |
101.1 |
45.1 |
138.7 |
269.4 |
399.3 |
274.8 |
220.4 |
137.0 |
|
MP2/aug-cc-pVTZ |
103.8 |
51.8 |
146.0 |
275.4 |
411.3 |
290.1 |
232.1 |
143.3 |
| 實驗值 |
103.3 |
55.7 |
149.3 |
266.8 |
392.4 |
276.7 |
219.4 |
135.4 |
Reference: Atkins' PHYSICAL CHEMISTRY
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|
Absolute error of atomization energy |
unit(kcal/mol) |
H2 |
LiH |
BeH2 |
BH3 |
CH4 |
NH3 |
H2O |
HF |
MAE |
RMSE |
|
|
B3LYP/6-31+G(d,p) |
-8.4 |
-1.3 |
-4.4 |
-19.9 |
-30.3118 |
-23.3093 |
-10.1877 |
-2.74954 |
12.57982 |
16.05635 |
|
|
B3LYP/aug-cc-pVTZ |
-6.9 |
-2.7 |
-1.5 |
-17.9 |
-28.1622 |
-23.8731 |
-11.1856 |
-3.38759 |
11.94395 |
15.31875 |
|
|
MP2/6-31+G(d,p) |
2.2 |
10.6 |
10.6 |
-2.7 |
-6.8471 |
1.983558 |
-1.05526 |
-1.61607 |
4.691977 |
6.036807 |
|
|
MP2/aug-cc-pVTZ |
-0.5 |
3.9 |
3.3 |
-8.7 |
-18.8989 |
-13.3642 |
-12.787 |
-7.89436 |
8.664215 |
10.38713 |
--> MP2/6-31+G(d,p) > MP2/aug-cc-pVTZ > B3LYP/aug-cc-pVTZ > B3LYP/6-31+G(d,p)