•Use Spartan or WebMO to calculate the ionization energy of atoms with atomic number 1~18, by using PM3、HF and MP2 theoretical method with 6-31G* basis set, and do some simple statistical analysis. The unit of the ionization energy is kcal/mol .

H到Ar的游離能圖:

理論值

理論與實際的誤差
 
結論:
1.同族元素，原子序越大IE值越小(第一游離能定義為氣態原子失去一個電子成為一價氣態正離子所需的最低能量，記作IE)
2.PM3無法計算8A族元素

Practise to use Spartan or WebMO to bulid the molecular structure, and try to optimize and calculate the job which you created.

參考資料:
https://physics.nist.gov/PhysRefData/ASD/ionEnergy.html
彭教授金屬串(WebMO)