1. Applying the mobility (scatter effect) of electrons and holes.
2. Electric conductivity can be evaluated by estimating the carrier density inclusive of the mobility of electrons and holes (effective carrier density), which is beyond the reach of conventional band theory. In addition to the physical quantities (such as band gap, ionizing potential and electron affinity) obtained by the conventional band calculation, the following physical quantities can also be calculated:

1. Band structure inclusive of electron transport characteristics
2. Density of state (ET DOS) in the ET band structure
3. The number of electrons contributing to electron transport (effective number of electrons)
4. Carrier density inclusive of mobility of electrons and holes (effective carrier density)

Capable of identifying carriers and bands that contribute to electric conductivity and discovering their features, the ET band method can analyze the conductivity mechanism in conductive polymer and crystal materials, and permits molecular designing of new conductive materials. The following are some applications:

1. Calculation of effective number of electrons for combination exchangeability in polyvinylene and polyacetylene
2. Calculation of ET DOS of soliton in polyacetylene
3. Calculation of electronic state of doped polyacetylene
4. Calculation of effective carrier density of polythiazyle, a superconductor