M2L6b.txt

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Let's talk now about some general properties of one
electron atoms with cores.

A lot of research in our field is done with alkali atoms.
Alkali atoms are not the hydrogen atom,
but they have one outer electron.
So they are hydrogen-like and now we want to sort of figure
out what is the main difference
between one outer electron in rubidium and sodium
and the sole electron in hydrogen.
Well if we have an electron, and this electron orbits around
in the alkali atom.
There is an ionic core which has a charge of z plus,
but then in this sort of compact core,
they are also Z minus 1 electron.
So the electron-- the outer electron pretty much
feels the electric field of a single charge,
but there is a presence of the core.
So what I want to discuss with you
is now what is the leading correction
to the properties of this atom.
What is the leading correction to the hydrogen-like wave
function due to the fact that we have an ionic core and not
a proton.
For hydrogen, we would have the Rydberg formula
that for principal quantum number, n,
the energy is Z square times the Rydberg constant divided
by n square.

So this would simply be what an electron would do in the Coulomb field of a single charge.