Atomic and nuclear properties of materials:
Technetium (Tc)

Quantity	Value	Units	Value	Units
Atomic number	43
Atomic mass	[97.90722(3)]	g mole-1
Density	11.5	g cm-3
Mean excitation energy	428.0	eV
Minimum ionization	1.325	MeV g-1cm2	15.24	MeV cm-1
Nuclear collision length	93.5	g cm-2	8.132	cm
Nuclear interaction length	156.8	g cm-2	13.64	cm
Pion collision length	118.1	g cm-2	10.27	cm
Pion interaction length	184.7	g cm-2	16.06	cm
Radiation length	9.58	g cm-2	0.8331	cm
Critical energy	13.46	MeV (for e-)	13.01	MeV (for e+)
Molière radius	15.09	g cm-2	1.313	cm
Plasma energy	64.76	eV
Muon critical energy	232.	GeV
Melting point	2430.	K	2157.	C
Boiling point @ 1 atm	4538.	K	4265.	C

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
Note: Since there is no stable isotope, [atomic mass] is that of the longest-lived known isotope as of Jan 2007.
Table of isotopes Warning: may not be current
x ray mass attenuation coefficients