L-Asparagine crystals with wide gap semiconductor features : optical absorption measurements and density functional theory computations
Autor(a) principal: | |
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Data de Publicação: | 2014 |
Outros Autores: | , , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UFRGS |
Texto Completo: | http://hdl.handle.net/10183/179089 |
Resumo: | Results of optical absorption measurements are presented together with calculated structural, electronic, and optical properties for the anhydrous monoclinic L-asparagine crystal. Density functional theory (DFT) within the generalized gradient approximation (GGA) including dispersion effects (TS, Grimme) was employed to perform the calculations. The optical absorption measurements revealed that the anhydrous monoclinic L-asparagine crystal is a wide band gap material with 4.95 eV main gap energy. DFT-GGA+TS simulations, on the other hand, produced structural parameters in very good agreement with X-ray data. The lattice parameter differences a, b, c between theory and experiment were as small as 0.020, 0.051, and 0.022 Å, respectively. The calculated band gap energy is smaller than the experimental data by about 15%, with a 4.23 eV indirect band gap corresponding to Z→ and Z→β transitions. Three other indirect band gaps of 4.30 eV, 4.32 eV, and 4.36 eV are assigned to α3→ , α1→ , and α2→ transitions, respectively. -sol computations, on the other hand, predict a main band gap of 5.00 eV, just 50 meV above the experimental value. Electronic wavefunctions mainly originating from O 2p–carboxyl, C 2p–side chain, and C 2p–carboxyl orbitals contribute most significantly to the highest valence and lowest conduction energy bands, respectively. By varying the lattice parameters from their converged equilibrium values, we show that the unit cell is less stiff along the b direction than for the a and c directions. Effective mass calculations suggest that hole transport behavior is more anisotropic than electron transport, but the mass values allow for some charge mobility except along a direction perpendicular to the molecular layers of L-asparagine which form the crystal, so anhydrous monoclinic L-asparagine crystals could behave as wide gap semiconductors. Finally, the calculations point to a high degree o |
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Zanatta, GeancarloGottfried, Carmem Juracy SilveiraSilva, Agmael MendonçaCaetano, Ewerton Wagner SantosSales, Francisco Adilson MatosFreire, Valder Nogueira2018-06-05T02:29:00Z20140021-9606http://hdl.handle.net/10183/179089001068178Results of optical absorption measurements are presented together with calculated structural, electronic, and optical properties for the anhydrous monoclinic L-asparagine crystal. Density functional theory (DFT) within the generalized gradient approximation (GGA) including dispersion effects (TS, Grimme) was employed to perform the calculations. The optical absorption measurements revealed that the anhydrous monoclinic L-asparagine crystal is a wide band gap material with 4.95 eV main gap energy. DFT-GGA+TS simulations, on the other hand, produced structural parameters in very good agreement with X-ray data. The lattice parameter differences a, b, c between theory and experiment were as small as 0.020, 0.051, and 0.022 Å, respectively. The calculated band gap energy is smaller than the experimental data by about 15%, with a 4.23 eV indirect band gap corresponding to Z→ and Z→β transitions. Three other indirect band gaps of 4.30 eV, 4.32 eV, and 4.36 eV are assigned to α3→ , α1→ , and α2→ transitions, respectively. -sol computations, on the other hand, predict a main band gap of 5.00 eV, just 50 meV above the experimental value. Electronic wavefunctions mainly originating from O 2p–carboxyl, C 2p–side chain, and C 2p–carboxyl orbitals contribute most significantly to the highest valence and lowest conduction energy bands, respectively. By varying the lattice parameters from their converged equilibrium values, we show that the unit cell is less stiff along the b direction than for the a and c directions. Effective mass calculations suggest that hole transport behavior is more anisotropic than electron transport, but the mass values allow for some charge mobility except along a direction perpendicular to the molecular layers of L-asparagine which form the crystal, so anhydrous monoclinic L-asparagine crystals could behave as wide gap semiconductors. Finally, the calculations point to a high degree oapplication/pdfengThe journal of chemical physics. Lancaster. Vol. 140, no. 12 (Mar. 2014), 124511, [15 p.]Ácido aspárticoAsparaginaL-Asparagine crystals with wide gap semiconductor features : optical absorption measurements and density functional theory computationsEstrangeiroinfo:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/openAccessreponame:Repositório Institucional da UFRGSinstname:Universidade Federal do Rio Grande do Sul (UFRGS)instacron:UFRGSORIGINAL001068178.pdf001068178.pdfTexto completo (inglês)application/pdf3358920http://www.lume.ufrgs.br/bitstream/10183/179089/1/001068178.pdfa0044873c9219772f311310a47ce4a6dMD51TEXT001068178.pdf.txt001068178.pdf.txtExtracted Texttext/plain72494http://www.lume.ufrgs.br/bitstream/10183/179089/2/001068178.pdf.txt3199da7b4887cd00b922748b5beef7c8MD5210183/1790892023-12-10 04:21:28.768889oai:www.lume.ufrgs.br:10183/179089Repositório de PublicaçõesPUBhttps://lume.ufrgs.br/oai/requestopendoar:2023-12-10T06:21:28Repositório Institucional da UFRGS - Universidade Federal do Rio Grande do Sul (UFRGS)false |
dc.title.pt_BR.fl_str_mv |
L-Asparagine crystals with wide gap semiconductor features : optical absorption measurements and density functional theory computations |
title |
L-Asparagine crystals with wide gap semiconductor features : optical absorption measurements and density functional theory computations |
spellingShingle |
L-Asparagine crystals with wide gap semiconductor features : optical absorption measurements and density functional theory computations Zanatta, Geancarlo Ácido aspártico Asparagina |
title_short |
L-Asparagine crystals with wide gap semiconductor features : optical absorption measurements and density functional theory computations |
title_full |
L-Asparagine crystals with wide gap semiconductor features : optical absorption measurements and density functional theory computations |
title_fullStr |
L-Asparagine crystals with wide gap semiconductor features : optical absorption measurements and density functional theory computations |
title_full_unstemmed |
L-Asparagine crystals with wide gap semiconductor features : optical absorption measurements and density functional theory computations |
title_sort |
L-Asparagine crystals with wide gap semiconductor features : optical absorption measurements and density functional theory computations |
author |
Zanatta, Geancarlo |
author_facet |
Zanatta, Geancarlo Gottfried, Carmem Juracy Silveira Silva, Agmael Mendonça Caetano, Ewerton Wagner Santos Sales, Francisco Adilson Matos Freire, Valder Nogueira |
author_role |
author |
author2 |
Gottfried, Carmem Juracy Silveira Silva, Agmael Mendonça Caetano, Ewerton Wagner Santos Sales, Francisco Adilson Matos Freire, Valder Nogueira |
author2_role |
author author author author author |
dc.contributor.author.fl_str_mv |
Zanatta, Geancarlo Gottfried, Carmem Juracy Silveira Silva, Agmael Mendonça Caetano, Ewerton Wagner Santos Sales, Francisco Adilson Matos Freire, Valder Nogueira |
dc.subject.por.fl_str_mv |
Ácido aspártico Asparagina |
topic |
Ácido aspártico Asparagina |
description |
Results of optical absorption measurements are presented together with calculated structural, electronic, and optical properties for the anhydrous monoclinic L-asparagine crystal. Density functional theory (DFT) within the generalized gradient approximation (GGA) including dispersion effects (TS, Grimme) was employed to perform the calculations. The optical absorption measurements revealed that the anhydrous monoclinic L-asparagine crystal is a wide band gap material with 4.95 eV main gap energy. DFT-GGA+TS simulations, on the other hand, produced structural parameters in very good agreement with X-ray data. The lattice parameter differences a, b, c between theory and experiment were as small as 0.020, 0.051, and 0.022 Å, respectively. The calculated band gap energy is smaller than the experimental data by about 15%, with a 4.23 eV indirect band gap corresponding to Z→ and Z→β transitions. Three other indirect band gaps of 4.30 eV, 4.32 eV, and 4.36 eV are assigned to α3→ , α1→ , and α2→ transitions, respectively. -sol computations, on the other hand, predict a main band gap of 5.00 eV, just 50 meV above the experimental value. Electronic wavefunctions mainly originating from O 2p–carboxyl, C 2p–side chain, and C 2p–carboxyl orbitals contribute most significantly to the highest valence and lowest conduction energy bands, respectively. By varying the lattice parameters from their converged equilibrium values, we show that the unit cell is less stiff along the b direction than for the a and c directions. Effective mass calculations suggest that hole transport behavior is more anisotropic than electron transport, but the mass values allow for some charge mobility except along a direction perpendicular to the molecular layers of L-asparagine which form the crystal, so anhydrous monoclinic L-asparagine crystals could behave as wide gap semiconductors. Finally, the calculations point to a high degree o |
publishDate |
2014 |
dc.date.issued.fl_str_mv |
2014 |
dc.date.accessioned.fl_str_mv |
2018-06-05T02:29:00Z |
dc.type.driver.fl_str_mv |
Estrangeiro info:eu-repo/semantics/article |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/10183/179089 |
dc.identifier.issn.pt_BR.fl_str_mv |
0021-9606 |
dc.identifier.nrb.pt_BR.fl_str_mv |
001068178 |
identifier_str_mv |
0021-9606 001068178 |
url |
http://hdl.handle.net/10183/179089 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.ispartof.pt_BR.fl_str_mv |
The journal of chemical physics. Lancaster. Vol. 140, no. 12 (Mar. 2014), 124511, [15 p.] |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
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Repositório Institucional da UFRGS |
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