Question

I just started reading about the conduction mechanism in polymer. From what i read, polarons are used as method of charge transportation in non-degenerate polymer. While for degenerate polymer, both charged soliton and polaron will do the job.

As i go a bit deeper, polaron can be defined as:

A polaron can be thought of as a bound state of a charged soliton and a neutral soliton of which the midgap energy states hybridize to form bonding and antibonding levels.
A Quasiparticle that is created through the interaction of charged particles ( electron or holes ) with Phonon.
If i understand it correctly, the definition of the polaron contradicts with its existance in non-degenerate polymer as non-degenerate polymer doesnt have soliton due to its topological reason.

Also, as i am quite new to all these terms (polaron, bipolaron, soliton, charged soliton and phonon), i tend to get confuse and couldnt differentiate each of them precisely in layman terms as most of the literature are mostly explained in what could say too academic for a starter like me.

Answer 1

Polarons in non-degenerate polymers are quasiparticles resulting from the interaction with phonons and do not require solitons for their existence, differentiating from the charged solitons found in degenerate polymers.

Step-by-step explanation:

In non-degenerate polymers, charge transport is primarily facilitated via polarons, which are quasiparticles that arise from the interaction of electrons or holes with the lattice phonons (vibrations) of the polymer. These polarons do not require the presence of solitons to exist; they are distinct entities within the material.

This does not contradict their existence in non-degenerate polymers, as their formation mechanism is different from that of solitons. The key to understanding this is the awareness that polarons and solitons are different models for describing charge transport in polymers, and their applicability depends on the electronic structure and polymer chain configuration.

On the other hand, degenerate polymers can utilize both charged solitons and polarons for charge transport. Charged solitons are associated with a topological feature of the polymer chain, whereas polarons are more associated with the charge-phonon interaction without requiring a specific topology.

Therefore, charged solitons are not required for the formation of polarons. To better differentiate these terms, consider a polaron as a charge interacting with the polymer's atomic vibrations, while a soliton is a domain wall or defect that carries charge in conjugated systems with the appropriate topology.