Quantum Mechanics 3 Flashcards
What are the assumptions of the free electron model
The electrons are non interacting, independent, and not bound to an atom (ex. If conjugated chain, electrons are delocalized around it)
The electrons have 0 potential energy in the inside of the conjugated system, and infinite outside
Electrons have 1/2 spin and two may occupy each energy level
How many pm per bond and per lone pair
140pm/bond
70pm/lone pair (end of chain)
What is special about the homo and lumo
The longest wavelength absorption is for an electron going from homo to lumo
How do you calculate the energy of a linear conjugated chain
Find L (box length) using 140 and 70
Find the number of pi electrion to find the levels of homo and lumo
Use E= pi^2h^2/2m (n^2/L^2)
n^2 is found by lumo^2 - homo^2
E is in Joules
How do you find the wavelength of a conjugated liner chain electron
Wavelength = hc/E
What is the trend for conjugated liner systems
The longer the chain means higher Lc meaning lower E, meaning higher wavelength
What are the three types of potential
The infinite potential well (
Parabolic potential well (characterizes vibrational levels)
Finite potential well (the electron wave function can break out)
What is the finite potential wells implication to waves
Transmission
Continuity
Energetically classically forbidden
What is special about the infinite potential well in relation to an electron
The electron exists as a wave within the well
It can leak out past the boundary’s in the form of an electron .
After leakage it can be measured and found as a particle near the boundary of the other well
What is tunneling behaviour in protiens
an electron in a protien can move to another protien though tunneling
This can happen as long as a wave extends out to a region where the electron can go
