In a previous paper we studied an injected electron-hole pair in crystalline polyethylene (PE) and found that the exciton becomes weakly self-trapped in a narrow interchain pocket comprised between two gauche defects. Despite the large energy stored in the trapped excitation, there did not appear to be a direct nonradiative channel for electron-hole recombination. Actual polyethylene systems of practical use are, however, neither crystalline nor pure. To understand the fate of an electron-hole pair in the impure case, we studied by ab initio simulations the evolution of an exciton trapped on three common chemical defects found in polyethylene: a grafted carbonyl (C=O); an intrachain vinyl group (C=C); a grafted carboxyl (COOH). Ab initio simulations lead to predict three different outcomes: trapping, nonradiative recombination, and homolitic bond-breaking, respectively. This suggests that extrinsic self-trapping of electron-hole pairs over chemical defects inside the quasicrystalline fraction of PE could be relevant for electrical damage in high-voltage cables.
%0 Journal Article
%1 ceresoli2004trapping
%A Ceresoli, Davide
%A Tosatti, Erio
%A Scandolo, Sandro
%A Santoro, G
%A Serra, S
%D 2004
%I AIP
%J The Journal of chemical physics
%K EDFT excitons theory
%N 13
%P 6478--6484
%T Trapping of excitons at chemical defects in polyethylene
%V 121
%X In a previous paper we studied an injected electron-hole pair in crystalline polyethylene (PE) and found that the exciton becomes weakly self-trapped in a narrow interchain pocket comprised between two gauche defects. Despite the large energy stored in the trapped excitation, there did not appear to be a direct nonradiative channel for electron-hole recombination. Actual polyethylene systems of practical use are, however, neither crystalline nor pure. To understand the fate of an electron-hole pair in the impure case, we studied by ab initio simulations the evolution of an exciton trapped on three common chemical defects found in polyethylene: a grafted carbonyl (C=O); an intrachain vinyl group (C=C); a grafted carboxyl (COOH). Ab initio simulations lead to predict three different outcomes: trapping, nonradiative recombination, and homolitic bond-breaking, respectively. This suggests that extrinsic self-trapping of electron-hole pairs over chemical defects inside the quasicrystalline fraction of PE could be relevant for electrical damage in high-voltage cables.
@article{ceresoli2004trapping,
abstract = {In a previous paper we studied an injected electron-hole pair in crystalline polyethylene (PE) and found that the exciton becomes weakly self-trapped in a narrow interchain pocket comprised between two gauche defects. Despite the large energy stored in the trapped excitation, there did not appear to be a direct nonradiative channel for electron-hole recombination. Actual polyethylene systems of practical use are, however, neither crystalline nor pure. To understand the fate of an electron-hole pair in the impure case, we studied by ab initio simulations the evolution of an exciton trapped on three common chemical defects found in polyethylene: a grafted carbonyl (C=O); an intrachain vinyl group (C=C); a grafted carboxyl (COOH). Ab initio simulations lead to predict three different outcomes: trapping, nonradiative recombination, and homolitic bond-breaking, respectively. This suggests that extrinsic self-trapping of electron-hole pairs over chemical defects inside the quasicrystalline fraction of PE could be relevant for electrical damage in high-voltage cables.},
added-at = {2019-02-07T17:58:18.000+0100},
author = {Ceresoli, Davide and Tosatti, Erio and Scandolo, Sandro and Santoro, G and Serra, S},
biburl = {https://www.bibsonomy.org/bibtex/2fa68b4daf573062db908cbdfa684759a/skoerbel},
interhash = {c3da09a15755d500140e437754b769f5},
intrahash = {fa68b4daf573062db908cbdfa684759a},
journal = {The Journal of chemical physics},
keywords = {EDFT excitons theory},
number = 13,
pages = {6478--6484},
publisher = {AIP},
timestamp = {2019-02-07T17:58:18.000+0100},
title = {Trapping of excitons at chemical defects in polyethylene},
volume = 121,
year = 2004
}