Abstract
I propose kinetically determined topological models of lightly doped (x0.05) amorphous (Ge,Si)1xYx alloys (Y=H,F,B,P,). Without adjustable parameters the model relates the lowest concentration xH0 of hydrogen atoms required to quench paramagnetic dangling bonds to the concentration c0 of unpaired spins at x=0. Also discussed are the structural differences between freshly evaporated α-(Ge, Si) and various stages of ion-bombarded ("amorphized") crystalline material.