Atomic and nuclear properties of einsteinium (Es)
Atomic number 99  
Atomic mass [252.0830(4)] g mole-1
Specific gravity ?? g cm-3
Mean excitation energy 980.0 eV
Minimum ionization 1.102 MeV g-1cm2
Nuclear collision length 120.5 g cm-2
Nuclear interaction length 213.0 g cm-2
Pion collision length 143.4 g cm-2
Pion interaction length 239.1 g cm-2
Radiation length 5.61 g cm-2
Critical energy 6.47 MeV (for e-)
Molière radius 18.37 g cm-2
Plasma energy ωp 67.57 eV
Muon critical energy 123. GeV
Melting point 1133. K
For muons, dE/dx = a(E) + b(E) E. Tables of b(E): PDF TEXT
Table of muon dE/dx and Range: PDF TEXT
Explanation of some entries
Note: Since there is no stable isotope, [atomic mass] is that of the longest-lived isotope known as of Jun 2017.
Note: Density 14.0 g/cm3 and Ieff = 980 eV assumed in calculating critical energies and dE/dx.
Table of isotopes via WIKIPEDIA