What are the units of the radial wavefunction in my FORTRAN code?

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The discussion focuses on the normalization of the radial wavefunction for the Hydrogen atom in a FORTRAN implementation. The user is comparing their numerical solution, obtained using the backward Euler method, with an analytical solution for the wavefunction. They express confusion regarding the units of the radial wavefunction, particularly whether the units should be keV^(1/2) or keV^-1, given that they are working in natural units. It is clarified that the radial wavefunction's normalization requires it to have units consistent with r^-3, leading to a need for careful consideration of units in the code. The user seeks advice on how to represent units in their graphs, highlighting a common challenge in understanding wavefunction normalization.
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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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The radial part of the wave function is normalized according to
$$
\int_0^\infty R_{nl}(r) r^2 \, dr = 1
$$
which means that ##R_{nl}## has the same units as ##r^{-3}##.
 
Time reversal invariant Hamiltonians must satisfy ##[H,\Theta]=0## where ##\Theta## is time reversal operator. However, in some texts (for example see Many-body Quantum Theory in Condensed Matter Physics an introduction, HENRIK BRUUS and KARSTEN FLENSBERG, Corrected version: 14 January 2016, section 7.1.4) the time reversal invariant condition is introduced as ##H=H^*##. How these two conditions are identical?

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