Total angular momentum quantum number
From Biocrawler, the free encyclopedia.
In atomic physics, the total angular quantum momentum numbers parameterize the total angular momentum of a given electron, by combining its orbital angular momentum and its intrinsic angular momentum (i.e., its spin).
If s is the electron spin angular momentum and l its orbital angular momentum vector, the total angular momentum j is
The associated quantum number is the main total angular momentum quantum number j. It can take the following values:
where l is the azimuthal quantum number (parameterizing the orbital angular momentum) and s is the spin quantum number (parameterizing the spin).
The relation between the total angular momentum vector j and the total angular momentum quantum number j is given by the usual relation (see angular momentum quantum number)
the vector's z-projection is given by
where mj is the secondary total angular momentum quantum number. It ranges from −j to +j in steps of one. This generates 2j + 1 different values of mj.
See also
- principal quantum number
- orbital angular momentum quantum number
- magnetic quantum number
- spin quantum number
- angular momentum coupling
External links
- Vector model of angular momentum (http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/vecmod.html)
- LS and jj coupling (http://hyperphysics.phy-astr.gsu.edu/hbase/atomic/lcoup.html#c1)

