Physics – Condensed Matter – Materials Science
Scientific paper
2003-05-14
Physics
Condensed Matter
Materials Science
17 pages, 2 figures
Scientific paper
10.1088/0953-8984/15/22/307
The complex band structure of an isolated polyethylene chain is calculated within Density Functional Theory (DFT). A plane wave basis and ultrasoft pseudopotentials are used. The results are compared with those obtained via a local basis set. We obtain a gap between the highest occupied molecular orbilar (HOMO) and the antibonding unoccupied molecular orbitals of 9.3 eV and a non-resonant tunneling $\beta$ parameter of 0.9 per monomer, in reasonable agreement with experiment and with results obtained via local basis. Polyethylene is a negative electron affinity material and the actual gap should be the energy of the HOMO with respect to the vacuum level (in DFT approximation only about 5.14 eV). The Bloch states at imaginary k are mainly free-electron-like parabolic bands which are missing in the local basis. We present also the complex bands of the bulk polyethylene in order to estimate the effects of the chain-chain interactions on the complex band structure. The relevance of these results for the tunnelling conduction of n-alkane chains is discussed.
Corso Andrea Dal
Picaud Fabien
Smogunov Alexander
Tosatti Erio
No associations
LandOfFree
Complex Band Structures and Decay Length in Polyethylene Chains does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Complex Band Structures and Decay Length in Polyethylene Chains, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Complex Band Structures and Decay Length in Polyethylene Chains will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-80679