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PHYS 342 Modern Physics Atom V: Many –Electron Atoms
Today Contents:a) Pauli Exclusion Principleb) Electron States in Many‐Electron Atomsc) Outer Electron and Optical Transition
Pauli Exclusion Principle
Fundamental principle -- Pauli Exclusion PrincipleAny fundamental particles with Odd/2 spin can not have the same set of quantum numbers in a quantum system.
No two electrons can have the same set of quantum number (n, l , ml, s , ms ) in a single atom.
Occupation Number of Atomic States
( n, l , ml, s , ms )energy Level
orbitalAM
z‐orbitalAM2 1
spinAM
z‐spinAM2
## 2 2 1
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ml=0 ml=0
Electron ConfigurationsShow the electrons in orbitals–Box used to represent orbital–Half arrow used to represent e‐ with opposite spins
Electrons are placed in orbitals of lowest energy first
Electron Configuration
Carbon: 1 2 2
1s
2s
3s3p
2p
The correct way: Use sum of n+l to determine which orbital fills first.
Rule#1.
Naive thinking: The energy increases from the smaller n to the larger n. For the same n, from the smaller p to the larger p.
It is wrong!
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1s
2s
3s3p
2p
1s
2s
3s3p
2pLi C
Rule#2: The electron prefers to occupy different ml states first.
Minor Variation: Half filling and Full Filling
Rule#3
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1s 2s 2p 3s 3p
(1 0 0) (2 0 0) (2 1 -1), (2 1 0), (2 1 1) ? ? ? ?
(n, l, ml)
4s 3d
? ? ? ? ? ?
Write down the full electron configuration use
ICP 31
Nickel-28 Electron Configuration and quantum numbers
#
1 ? ? ? ? ?
The Periodic TableFive basic category: Inert gas (Full p-shell), p-subshell,
S-subshell, Transition Metals (d-shell filled first than p-shell)
Lanthanides and Actinides (f-shell filled first than d-shell)https://www.youtube.com/watch?v=xqoQfN9DgNs
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Outer Electron
Li2s electron (-e)
Hydrogen-like atom
and
Effective Nuclei Charge (Ze)
ICP 32
If the effective nuclear charge for lithium n=2 orbit electron is 1.26e, then what is the ionization energy for lithium atom n=2 electron. (use eV in your answer)
Periodic Physical Properties Periodic Physical Properties
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Periodic Physical Properties Li Energy Level and Spectrum
wavelengths in the range of 350nm – 1000 nm
Ground state of the outermost electron shell (2s1):
2 / 2 /
2 /
Optical TransitionThe transition of outer electron between the ground and excited states make the atom emits/absorbed light.
Li: 1 2 Na: 1 2 2 3
Spectrum- tool for atomic world
https://www.youtube.com/watch?v=RFFfYlq3oEoTransient Absorption Spectroscopy
https://www.youtube.com/watch?v=pxC6F7bK8CUspectrophotometer
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EXAM 2 (Monday March 21rd)
a) 3 steps to solve Schrodinger Equation b) 6 special cases for Schrodinger Equation (free particles. Infinite potential well, finite potential well, potential barrier, potential step, simple harmonic oscillator)c) 2 models for hydrogen atom: Rutherford Model and Bohr Model d) 3 probability of for hydrogen atom wave function: angular probability , radial probability, probability density e) 3 angular momentum and magnetic dipole: orbital, spin and total f) 7 Quantum Numbersg) 3 rules to fill the electron statesh) 1 method: how to add angular momentum
HW8
HW8: Chapter 8- P 3,7,11,18
ICP 31-32
http://webphysics.iupui.edu/342/phy342sp16/calendar.htm
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