Atomic and nuclear properties of materials:
Polypropylene ([CH(CH₃)CH₂]_n)

Quantity	Value	Units	Value	Units
<Z/A>	0.55998
Density	0.905	g cm-3
Mean excitation energy	57.4	eV
Minimum ionization	2.041	MeV g-1cm2	1.847	MeV cm-1
Nuclear collision length	56.1	g cm-2	62.01	cm
Nuclear interaction length	78.5	g cm-2	86.72	cm
Pion collision length	83.7	g cm-2	92.51	cm
Pion interaction length	110.4	g cm-2	122.0	cm
Radiation length	44.77	g cm-2	49.47	cm
Critical energy	99.80	MeV (for e-)	97.18	MeV (for e+)
Molière radius	9.51	g cm-2	10.51	cm
Plasma energy	20.51	eV
Muon critical energy	1259.	GeV

Composition:

Elem	Z	Atomic frac*	Mass frac*
H	1	2.00	0.143711
C	6	1.00	0.856289
* calculated from mass fraction data.

Explanation of some entries
For muons, dE/dx = a(E) + b(E) E. Tables of b(E): PS PDF TEXT
Table of muon dE/dx and Range: PS PDF TEXT
Note: Chem formula wrong in Sternheimer. I and density effect constants
for polyethylene, scaled with density, were used for these calculations.