  A theoretical model is provided to address the parameters influencing the
electronic properties of kink-structured carbon chain at 0K. It is studied by
the principle of DFT and solving the numerical 1D time-independent
Schr\"odinger equation of electron and phonon simultaneously. Two different
lengths of branches A and B, are occupied alternatively to generate the
asymmetric carbon chain. The ratio of the asymmetric branch length,RAB=A/B,
plays an important role in the electronic density of states DOS around Fermi
level Ef . The highest DOS(Ef) occurs if the RAB equals to 2 and while the
Fermi level coincides with the Von-Hove singularity at RAB=3. The location of
the singularity point relative to the Ef is controllable via branch length
interestingly. By comparison with the symmetric case, tuning the branch length
asymmetrically shows a stronger impact to shift the Ef to the singularity
point. The numerical solution of the 1D time independent Schrodinger equation
of phonon indicates that the kink reinforces the charge fluctuations but the
fluctuations are minimized when the RAB goes up. Based on the simulation
results, the electron phonon coupling of the carbon nanowire decreases with
chain length. In comparison to the symmetric structure, the electron phonon
coupling of the asymmetric carbon chain is higher. The maximum electron phonon
coupling of the asymmetric carbon chain takes place at RAB=2 . However, the
weakening of the electron phonon coupling is observed owing to ultrahigh
concentration of kinks. The reduction of the electron phonon coupling of the
carbon chain is occurred under pressure.
