Stephen,
1) 7Li --> 4He + 3H requiring -2.43 MeV (endotherm) of mass-energy
and then there is:
2) D + D --> 3H(1.01 MeV) + 1H(3.02 MeV)
This indicates that we _might_ expect 4MeV per tritium atom.
Not really - if the two reactions are (approximately) interlocking and mutually dependent (in the sense of high probability).
All but ~600 keV for the proton is lost - and then the rest divided between the two tritium's - so there is a net of ~800 keV per tritium produced - not exactly chump change but over five times less than would be expected from straight fusion of deuterium.
Jones
