How Do Units Affect Hydrogen Wavefunction Normalization in FORTRAN?

AI Thread Summary
The discussion revolves around solving the Hydrogen wavefunction using FORTRAN and the challenges of normalizing it in natural units. The user compares results from the Euler method and the more accurate backwards Euler method, noting discrepancies in amplitude and shape. They express confusion regarding the units of the wavefunction, particularly how the analytic solution's normalization relates to their computed results. It is clarified that wavefunctions must have units of volume^-1/2 or length^-3/2 to satisfy the normalization condition. The conversation highlights the complexities of unit conversions in quantum mechanics, especially when working with different unit systems.
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I am solving the Hydrogen wavefunction using FORTRAN.
Now using the Euler method, I am given a solution to match which is given by u10(r) = 1.06r*exp(-3.74r) (where unl(r) = rRnl(r) in general) which says it has a normalisation chosen to match what i should get from my code.

Then I use the backwards Euler method getting a more accurate solution with a correct shape and a much larger amplitude. I then normalise this and plot it against the analytic solution given by
u = 1/pi^1/2*(1/ao)^3/2*r*exp(-r/a0) which is apparently also normalised.

I am working in natural units so h-bar = c = 1 and me = 511.7keV the electron mass, which implies that my Bohr radius = 0.26737keV^-1 and I am working in units of r given by keV^-1 also.

so this would imply that the units of u for the analytic solution must be keV^(1/2) however looking at the original equation shouldn't the units be keV^-1 as u = rR(r) where r has units keV^-1 and R(r) is dimensionless, I'm confused. Is my normalisation unit calculated in fortran supposed to have units like the analytic normalisation constant?

On my graphs should I just put no units? :S
Any suggestions would be appreciated, units of wavefunctions has always confused me.
 
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Wavefunction units can be tricky, but you can get it from the normalization condition:
∫ Ψ*Ψ dx dy dz = 1​
Since the "1" is dimensionless, and "dx dy dz" is a volume, the wavefunction must have units of volume-1/2 or length-3/2
 
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