Cấu hình theo phân mức năng lượng 

$\rm Z=15: 1s^22s^22p^63s^23p^3$ 

$\rm Z=16:1s^22s^22p^63s^23p^4$ 

$\rm Z=17:1s^22s^22p^63s^23p^5$ 

$\rm Z=18:1s^22s^22p^63s^23p^6$ 

$\rm Z=19:1s^22s^22p^63s^23p^64s^1$ 

$\rm Z=20:1s^22s^22p^63s^23p^64^2$ 

$\rm Z=21: 1s^22s^22p^63s^23p^64s^23d^1$ 

$\rm Z=22: 1s^22s^22p^63s^23p^64s^23d^2$ 

$\rm Z=23: 1s^22s^22p^63s^23p^64s^23d^3$ 

$\rm Z=24: 1s^22s^22p^63s^23p^64s^13d^5$ 

$\rm Z=25: 1s^22s^22p^63s^23p^64s^23d^5$ 

$\rm Z=26:1s^22s^22p^63s^23p^64s^23d^6$ 

$\rm Z=27: 1s^22s^22p^63s^23p^64s^23d^7$ 

$\rm Z=28:1s^22s^22p^63s^23p^64s^23d^8$ 

$\rm Z=29:1s^22s^22p^63s^23p^64s^13d^{10}$ 

$\rm Z=30:1s^22s^22p^63s^23p^64s^23d^{10}$ 

Cấu hình `e` 

$\rm Z=15: 1s^22s^22p^63s^23p^3$ 

$\rm Z=16:1s^22s^22p^63s^23p^4$ 

$\rm Z=17:1s^22s^22p^63s^23p^5$ 

$\rm Z=18:1s^22s^22p^63s^23p^6$ 

$\rm Z=19:1s^22s^22p^63s^23p^64s^1$ 

$\rm Z=20:1s^22s^22p^63s^23p^64^2$ 

$\rm Z=21: 1s^22s^22p^63s^23p^63d^14s^2$ 

$\rm Z=22: 1s^22s^22p^63s^23p^63d^24s^2$ 

$\rm Z=23: 1s^22s^22p^63s^23p^63d^34s^2$ 

$\rm Z=24: 1s^22s^22p^63s^23p^63d^54s^1$ 

$\rm Z=25: 1s^22s^22p^63s^23p^63d^54s^2$ 

$\rm Z=26:1s^22s^22p^63s^23p^63d^64s^2$ 

$\rm Z=27: 1s^22s^22p^63s^23p^63d^74s^2$ 

$\rm Z=28:1s^22s^22p^63s^23p^63d^84s^2$ 

$\rm Z=29:1s^22s^22p^63s^23p^63d^{10}4s^1$ 

$\rm Z=30:1s^22s^22p^63s^23p^63d^{10}4s^2$ 

Bạn tham khảo: Z = 24 , Z = 29 người ta gọi đó là trạng thái bán bão hoà nha