Atomic and nuclear properties of materials:
Thallium (Tl)

Quantity	Value	Units	Value	Units
Atomic number	81
Atomic mass	204.3833(2)	g mole-1
Specific gravity	11.7	g cm-3
Minimum ionization	1.125	MeV g-1cm2	13.19	MeV cm-1
Nuclear collision length	113.6	g cm-2	9.696	cm
Nuclear interaction length	198.7	g cm-2	16.96	cm
Radiation length	6.42	g cm-2	0.5477	cm
Critical energy	7.50	MeV (for e-)	7.23	MeV (for e+)
Molière radius	18.15	g cm-2	1.549	cm
Plasma energy	62.10	eV
Muon critical energy	142.	GeV

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
Explanation of some entries
Table of isotopes
x ray mass attenuation coefficients