Hyperfine coupling for a spin-one nucleus
= Hyperfine coupling for a spin-one nucleus
For <electron spin> $s=1/2$, first add orbital and spin angular momenta to obtain $j=L\pm1/2$. For <nuclear spin> $I=1$, add again to obtain $F=|j-1|,|j-1|+1,\ldots,j+1$. The projection has $2F+1$ possible values. A hydrogenic bound state still requires $L\leq n-1$.