  Rigidity Percolation is studied analytically on randomly bonded networks with
two types of nodes, respectively with coordination numbers $z_1$ and $z_2$, and
with $g_1$ and $g_2$ degrees of freedom each. For certain cases that model
chalcogenide glass networks, two transitions, both of first order, are found,
with the first transition usually rather weak. The ensuing intermediate pase,
although is not isostatic in its entirety, has very low self-stress. Our
results suggest a possible mechanism for the appearance of intermediate phases
in glass, that does not depend on a self-organization principle.

Disordered Systems and Neural Networks;Soft Condensed Matter