The Energy Band Structure of Polyacene with Soliton Excitation

1997 ◽  
Vol 11 (11) ◽  
pp. 477-483 ◽  
Author(s):  
Z. J. Li ◽  
H. B. Xu ◽  
K. L. Yao

Starting from the extensional Su–Schrieffer–Heeger model taking into account the effects of interchain coupling, we have studied the energy spectra and electronic states of soliton excitation in polyacene. The dimerized displacement u0 is found to be similar to the case of trans-polyacetylene, and equals to 0.04 Å. The energy-band gap is 0.38 eV, in agreement with the results derived by other authors. Two new bound electronic states have been found in the conduction band and in the valence band, which is different from the one of trans-polyacetylene. There exists two degenerate soliton states in the center of energy gap. Furthermore, the distribution of charge density and spin density have been discussed in detail.

2001 ◽  
Vol 79 (4) ◽  
pp. 749-756
Author(s):  
H F Hu ◽  
Y B Li ◽  
K L Yao

We have studied the energy band structure of polydiacetylenes (PDAs) using the extensional Hückel Hamiltonian that includes the nonnearest-neighbor hopping interactions. The results show that with increase in the nonnearest-neighbor hopping interaction parameters ρ1 and ρ2, (i) the energy band symmetry is broken and the energy gap 2Δ has changed, (ii) the locations and the widths of energy bands have changed and their shifts depend mainly on ρ1 (next-neighbor hopping interactions), and (iii) the energy gap 2Δ depends mainly on ρ2 (third-neighbor hopping interactions), the effects of the nonnearest-neighbor hopping interaction on the band structure are discussed. PACS No.: 31.15Ct


1996 ◽  
Vol 10 (19) ◽  
pp. 931-937 ◽  
Author(s):  
H.F. HU ◽  
K.L. YAO

Starting from the extensional model Hückel Hamiltonian containing the next-neighbor hopping interactions, the energy band structure and their variation have been studied for polydiacetylenes (PDA’s). With the increase of the next-neighbor hopping interaction parameter ρ the results show that: (1) the electronic state symmetry is broken, (2) the locations and the widths of energy bands have been changed, and (3) the energy gap becomes narrower and the total bandwidth broader. Finally, the effect of the nextneighbor hopping interactions on the band-structure is discussed.


1992 ◽  
Vol 247 ◽  
Author(s):  
Chizuko Tanaka ◽  
Jiro Tanaka

ABSTRACTThe optimized molecular structures of doped polyacetylene model compounds are studied by the ab initio SCF MO method. The calculated structures are assigned to polaron, charged soliton and poison unit. The one dimensional energy band structures of the charged soliton-antisoliton and the polson-antipolson lattices are investigated. The latter one gives a quasi-metallic energy band. The results of the energy band calculation are consistent with the electrical properties and ultraviolet photoemission spectra of the doped polyacetylene.


Author(s):  
Fikri Abdi Putra ◽  
Endhah Purwandari ◽  
Bintoro S. Nugroho

The properties of GaAs material in zinc blende type was calculated using Hiroshima Linear Plane Wave program based on the Density Functional Theory. This calculation aims to determine electronic properties of GaAs material are based on Density of States and energy band structure. This simulation’s results are DOS shows that hybridization of s orbital of Ga with s orbital of As provides covalent properties. The simulation of energy band structure from GaAs material indicates that semiconductor properties of GaAs is direct band gap. The energy band gap results obtained for GaAs is 0.80 eV. The computational result of the energy band gap calculation form HiLAPW has better accuracy and prediction with good agreement within reasonable acceptable errors when compared to some other DFT programs and the results of the experimental obtained.


RSC Advances ◽  
2015 ◽  
Vol 5 (124) ◽  
pp. 102173-102181 ◽  
Author(s):  
A. H. Reshak ◽  
Z. A. Alahmed ◽  
I. E. Barchij ◽  
M. Yu. Sabov ◽  
K. J. Plucinski ◽  
...  

The energy band structure, electronic charge density and optical features of Tl4PbSe3and Tl4PbTe3single crystals were studied within a framework of the recently modified Becke–Johnson potential (mBJ).


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