林昶廷-第10週作業1205

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•Calculate the first 13 excited states of the Hydrogen atom by using the CIS theoretical method with appropriate basis sets ( need to include diffuse functions or other elements ) then compare with the experimental values.

1.Table difference basis set calculation energy of first 13 excited states of the Hydrogen atom Unit :eV

Table.CIS theory to caculation Hydrogen

Unit eV excited state aug-cc-pVQZ d-aug-cc-pVQZ d-aug-cc-pVQZ+spd expt
2S 1 10.22 10.21 10.21 10.2
2P 2 10.86 10.21 10.21 10.2
3 10.86 10.21 10.21 10.2
4 10.86 10.21 10.21 10.2
3S 5 15.92 12.10 12.09 12.1
6 21.34 13.24 12.15 12.1
7 21.34 13.24 12.15 12.1
8 21.34 13.24 12.15 12.1
3D 9 21.34 13.38 12.16 12.1
10 21.34 13.38 12.16 12.1
11 23.46 13.38 12.16 12.1
12 23.46 13.38 12.16 12.1
13 23.46 13.38 12.16 12.1
　 MAE 6.62 0.76 0.04 　

 

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•Calculate the first 5 singlet excited states of Helium by using the CIS、CIS(D) theoretical method with appropriate basis sets then compare with the experimental values.

2.Table Using CIS  difference basis set calculation energy of first 5 excited states of the Helium atom

CIS Unit :eV
Unit eV excited state aug-cc-pVQZ  d-aug-cc-pVQZ d-aug-cc-pVQZ+spd expt
2S 1 21.4 21.1 21.1 20.6
2P 2 24.7 21.8 21.7 20.6
3 24.7 21.8 21.7 20.6
4 24.7 21.8 21.7 20.6
3S 5 34.9 23.8 23.8 21.2
　 MAE 5.4 1.3 1.3 　

 

2.Table Using CISD by difference basis set calculation energy of first 5 excited states of the Helium atom

CISD                                          Unit :eV  
Unit eV excited state aug-cc-pVQZ  d-aug-cc-pVQZ d-aug-cc-pVQZ+spd expt
2S 1 21.1 20.8 20.8 20.6
2P 2 24.3 21.5 21.5 20.6
3 24.3 21.5 21.5 20.6
4 24.7 21.5 21.5 20.6
3S 5 34.5 23.4 23.4 21.2
　 MAE 5.2 1.1 1.1 　

透過增加diffuse fuction 後可以發現計算值愈接近實驗值

 

Reference:     NIST Atomic Spectra Database