  We have studied the 4He(3He,gamma)7Be, 3He(3He,2p)4He, and 7Be(p,gamma)8B
reactions of the solar p-p chain, using microscopic cluster models. Among other
results, we showed that the 6Li+p channel has a nontrivial effect on the
7Be-producing reaction, that the existence of a resonance in 6Be close to the
3He+3He threshold is rather unlikely, and that the correlations between some
properties of 7Be/8B and the low-energy cross section of 7Be(p,gamma)8B might
help one to constrain the value of the S_17(0) astrophysical S-factor.
