1. Chapter – 1 Atomic Spectroscopy

2. (주기율표)
Group

3. Pauli Exclusion Principle (Pauli 배제 원칙)
The Pauli Exclusion Principle states that, in an atom or molecule, no two electrons can have the same four electronic quantum numbers. As an orbital can contain a maximum of only two electrons, the two electrons must have opposing spins.
Two electrons in a single orbital must have different values of ms
This statement demands that if there are two electrons in an orbital one must have ms = +1/2 (spin up ) and the other must have ms = -1/2 (spin down )
An electron in an orbital is fully described by the four quantum numbers: n, l, ml and ms

4. Quantum numbers (양자 수) are summarized as follows:
Name
Symbol
Orbital meaning
Range of values
Value examples
principal quantum
number n
shell
1 ≤ n
n = 1, 2, 3, …
azimuthal quantum number (angular
momentum) ℓ
subshell (s orbital is listed as 0, p orbital as 1
etc.)
0 ≤ ℓ ≤ n − 1
for n = 3: ℓ = 0, 1, 2 (s, p, d)
magnetic quantum
number, (projection of angular momentum) mℓ
energy shift (orientation of the subshell's shape)
−ℓ ≤ mℓ ≤ ℓ
for ℓ = 2: mℓ = −2, −1, 0, 1, 2
spin projection
quantum number ms
spin of the electron (−½ = "spin down",
½ = "spin up")
−s ≤ ms ≤ s
for an electron s = ½, so ms = −½, ½

8. Electronic configuration of Europium
Atomic Number
Electronic configuration - [Xe] 4f75d06s2
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 5d0 4f7
Orbit (n) orbital (s, p d f) Total Number of electrons s
s22p
s23p63d
s24p64d104f
s25p65d s
Total – 63 electrons
oxidation states (valence) - +2, +3

17. • Selection Rules for electric dipole transitions: ∆L = ±1, ∆S = 0, ∆J = 0, ±1 but not J = 0 to 0.
Fine Structure:
Atom in Magnetic Field
• Selection Rule for weak field: ∆MJ = 0, ±1 but not from 0 to 0