(2) Electrons in Atoms and Molecules Flashcards
See page 17 of document for a mathematical representation of a stationary state for a wave function
Do it
Describe the relationship between the following operators:
H, L^2, L_z
They all commute
- Can know them both simultaneously and precisely
Describe the range for E_n in terms of l
l = 0,1,2,… n-1
See page 17 of document for the equations for the energy eigenvalues and the potential of a hydrogen atom
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Briefly state the Pauli exclusion principle
Two fermions cannot occupy the same state in space unless they have different spin states
Describe the energy of the orbitals in terms of the orbital quantum number (l)
The energy of the orbitals increases as l increases
Describe the steps for electronic configurations
- Z electrons
- Each n state has n sub shells labelled by l e.g. n=3 has l = 0,1,2
- Each l subshell can take up to 2(2l+1) electrons. Start from lowest l and fill up
- 3d and 4s are close in energy, as are 4d, 5s, and 5d and 6s etc.
When solving problems involving molecules, what approximation do we make?
Neglect the nuclei’s KE
Describe the electronic and Coulomb energy of a nuclei
The nuclei are in the position of minimum electronic and nuclear Coulomb energy
- Electrons bond nuclei together in molecules
State the two types of bonding
- Covalent
- Ionic
Briefly describe covalent bonds
- Atoms share electron pairs
- Usually form between two or more non metals
Briefly describe ionic bonds
- Valence electrons are completely transferred
- Occur between metals and non-metals
See page 17 of document for the potential for a covalent bond graph
Do it
What is an anti-symmetric wave function?
One where the interchange of the coordinates of any two electrons changes the output sign of the wave function
See page 17 for an approximation for the Hamiltonian of Helium nucleus
Do it
