Atomic and nuclear properties of materials:
Roentgenium (Rg)
Atomic number 111  
Atomic mass [280.164(5)] g mole-1
Density ?? g cm-3
Mean excitation energy 1143.0 eV
Minimum ionization 1.091 MeV g-1cm2
Nuclear collision length 124.2 g cm-2
Nuclear interaction length 220.7 g cm-2
Pion collision length 146.8 g cm-2
Pion interaction length 246.5 g cm-2
Radiation length 5.14 g cm-2
Critical energy 5.88 MeV (for e-)
Molière radius 18.56 g cm-2
Plasma energy 67.87 eV
Muon critical energy 111. 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 are no stable isotopes, [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 Warning: may not be current