Energy gap  0.661 eV 
Energy separation (E_{Γ1})  0.8 eV 
Energy separation (ΔE>)  0.85 eV 
Energy spinorbital splitting  0.29 eV 
Intrinsic carrier concentration  2.0·10^{13} cm^{3} 
Intrinsic resistivity  46 Ω·cm 
Effective conduction band density of states  1.0·10^{19} cm^{3} 
Effective valence band density of states  5.0·10^{18} cm^{3} 
Band structures of Ge.

Energy gap narrowing versus donor (curve 1) and acceptor (curve 2) doping density. Open curves are experimental values. (Jain and Roulston [1991]) 
Electrons:  
The surfaces of equal energy are ellipsoids  
m_{l} = 1.59m_{o}  
m_{t} = 0.0815m_{o}  
Effective mass of density of states  
m_{c}=(9m_{l}m_{t}^{2})^{1/3}  m_{c}=0.22m_{o} 
Effective mass of conductivity  m_{cc}=0.12m_{o} 
Holes:  
Heavy  m_{h} = 0.33m_{o} 
Light  m_{lp} = 0.043m_{o} 
Splitoff band  m_{so} = 0.084m_{o} 
Effective mass of density of states  m_{v} = 0.34m_{o} 
As  P  Sb  Bi  Li 
0.014  0.013  0.010  0.013  0.093 
Al  B  Ga  In  Tl 
0.011  0.011  0.011  0.012  0.013 