hybridization. This creates a chain of alternating single and double bonds. The remaining orbitals overlap to form a delocalized -electron cloud.
Researchers are currently focusing on "n-type" (electron-transporting) materials, which are historically less stable and efficient than "p-type" (hole-transporting) materials. Summary for Researchers physics of organic semiconductors pdf
(pi) bonds. Alternating single and double bonds along a carbon chain create a . Within this system, the electrons in the hybridization
: Charges spend most of their time confined to individual molecules. Hopping Conduction Within this system, the electrons in the :
: When a charge moves, it often distorts the surrounding organic molecule, creating a "polaron"—a combination of the charge and its associated lattice distortion.
In inorganic semiconductors like silicon, atoms bond covalently into a rigid lattice, forming delocalized energy bands. Electrons occupy valence and conduction bands separated by a bandgap. In organic semiconductors, the physics is quite different. They consist of conjugated molecules or polymers—long chains of carbon atoms with alternating single and double bonds. This π-conjugation allows electrons to delocalize along the molecule, creating molecular orbitals: the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO). The HOMO–LUMO gap is the organic analog of the bandgap.