Atomic and nuclear properties of materials:
Roentgenium (Rg)
Atomic number 111  
Atomic mass [272.1536] g mole-1
Specific gravity ?? g cm-3
Minimum ionization 1.123 MeV g-1cm2
Nuclear collision length 123.2 g cm-2
Nuclear interaction length 218.6 g cm-2
Radiation length 5.00 g cm-2
Critical energy 5.87 MeV (for e-)
Molière radius 18.04 g cm-2
Plasma energy 68.86 eV
Muon critical energy 114. 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
Note: Since there is no stable isotope, given atomic mass is that of the longest-lived known isotope as of Jan 2007.
Note: Density 14.0 g/cm3 and Ieff = 1143 eV assumed in calculating critical energies and dE/dx.
Table of isotopes