What do you think about Feynman's description (http://feynmanlectures.caltech.edu/III_12.html#Ch12-S3) ? It seems to be inconsistent with hyperphysics (http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/h21.html).
The inconsistency is that hyperphysics says that the energy difference is due to spins going from parallel (higher energy) to antiparallel (lower energy) whereas according to Feynman antiparallel spins can be associated also with the higher energy. I don't see how hyperphysics can be correct if one considers also Zeeman splitting like Feynman does in the next section.try to summarize or point out which part of those long texts that you are concerned with.
Thanks, I think your description is consistent with Feynman's although you are using a slightly different notation. Also, your quoted text above is my summary of what Feynman actually said.##|F=1,m_F=0\rangle## is a symmetric combination between electron spin up-proton spin down and the opposite. I guess it's this last state which that hyperphysics link has omitted and which Feynman's lecture referred to as "antiparallel spins can be associated also with the higher energy".