Atomic and nuclear properties of materials:
UNCONFIRMED Element 118
Status of ultraheavies as of April 2010 (pdf)

Quantity	Value	Units	Value	Units
Atomic number	118
Atomic mass	[294.215(8)]	g mole-1
Specific gravity (20° C, 1 atm)	1.20E-02	g cm-3
Mean excitation energy	1242.0	eV
Minimum ionization	1.092	MeV g-1cm2	1.311E-02	MeV cm-1
Nuclear collision length	126.0	g cm-2	1.050E+04	cm
Nuclear interaction length	224.3	g cm-2	1.870E+04	cm
Pion collision length	148.5	g cm-2	1.237E+04	cm
Pion interaction length	250.1	g cm-2	2.084E+04	cm
Radiation length	4.88	g cm-2	406.9	cm
Critical energy	5.67	MeV (for e-)	5.45	MeV (for e+)
Molière radius	18.26	g cm-2	1521.	cm
Plasma energy	2.00	eV
Muon critical energy	131.	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: Atomic mass is that reported by the researchers as of Jan 2007.
Note: Density is for an ideal monotomic gas.
Note: I_eff = 1242 eV assumed in calculating critical energies and dE/dx.