PSi
Osugi, J.Namikawa, R.Tanaka, Y.
Reviews of Physical Chemistry of Japan (1966) 36, 35-43
a=5.241Å b=5.241Å c=5.241Å
α=90° β=90° γ=90°
P2Si
a=5.682Å b=5.682Å c=5.682Å