[Mark S 2014]

I get that the radial distribution function is the probability finding an electron in a shell of a thickness dr at radius r from the nucleus. What I don't get is what R(r)² dτ gives information about. Is this the probability of finding an electron in some sort of small circular volume at any point of radius r from the nucleus ? If so, then aren't they kind of the same thing but for different volumes ?

[mjc123]

For any given θ and φ, R(r)²dr is the probability of the electron being between r and r+dr.
The overall probability of its being between r and r+dr, i.e. of being in a spherical shell of radius r and thickness dr, is 4πr²R(r)²
The probability of its being in a volume element dτ at (r,θ,φ) is Ψ²dτ (or ΨΨ*dτ)
where the complete wavefunction Ψ = R(r)Θ(θ)Φ(φ)

[mjc123]

By the way, how did you get on with Rydberg?

[Mark S 2014]

Thanks again; that helped. Yes I was okay with it in the end, I just made the graph on excel and it came out with a straight line from which I was able to calculate the constant. My problem was that even though I was able to show that the frequencies all lay on the line, I had to assume that the transitions where all from certain n2 values. When I spoke to a lecturer the next day, he said there was a way of plotting a graph without assuming the transitions before hand - but the way I had answered it was fine. I still can't figure out a way of doing it without assuming the transitions before plotting a graph.

[Mark S 2014]

Thanks again for your help on those previous questions anyway, really appreciated.