Electronic, Structural and Vibrational Properties of GaP Diamondoids and Nanocrystals: A Density Functional Theory Study

The electronic, structural and vibrational properties of gallium phosphide diamondoids and nanocrystals were investigated using density functional theory at PBE/6-31(d) level, which included polarization functions. The energy gap obeyed the quantum confinement size effect with shape fluctuations. Th...

Full description

Bibliographic Details
Main Authors: Mudar Ahmed Abdulsattar, Bahjat B. Kadhim, Huda M. Jawad
Format: Article
Language:English
Published: Hindawi - SAGE Publishing 2015-05-01
Series:Nanomaterials and Nanotechnology
Subjects:
Online Access:http://www.intechopen.com/journals/nanomaterials_and_nanotechnology/electronic-structural-and-vibrational-properties-of-gap-diamondoids-and-nanocrystals-a-density-funct
_version_ 1797431896489066496
author Mudar Ahmed Abdulsattar
Bahjat B. Kadhim
Huda M. Jawad
author_facet Mudar Ahmed Abdulsattar
Bahjat B. Kadhim
Huda M. Jawad
author_sort Mudar Ahmed Abdulsattar
collection DOAJ
description The electronic, structural and vibrational properties of gallium phosphide diamondoids and nanocrystals were investigated using density functional theory at PBE/6-31(d) level, which included polarization functions. The energy gap obeyed the quantum confinement size effect with shape fluctuations. The gap converged towards its bulk limit at 2.26 eV. The Ga-P bond lengths of higher diamond‐ oids were found to be distributed around the bulk experi‐ mental value at 2.36 Angstrom. Tetrahedral angles were found around the ideal bulk zincblende value at 109.47, degrees while dihedral angles were distributed around the ideal bulk zincblende values at ±60 and ±180 degree. These findings illustrate that diamondoids are a good represen‐ tative of bulk structure. An analysis of vibrational modes, in terms of reduced masses, force constants and IR intensi‐ ty, was then performed. The size-related change of certain vibrational frequencies of GaP diamondoids was compared with the experimental bulk. Radial breathing mode frequency began from 187 cm-1 for the smallest molecule GaPH6 and decreased with fluctuations, heading to 0 cm-1 as its bulk limit. Longitudinal optical mode began from 187 cm-1 for the smallest molecule and increased with fluctua‐ tions, heading to 376.9 cm-1 (11.3 THz) as its bulk limit. Hydrogen-related vibrations were relatively constant and can therefore be used to identify GaP diamondoids because of their high IR and Raman intensity peaks.
first_indexed 2024-03-09T09:51:58Z
format Article
id doaj.art-7540261b26fc4e509d8b93f3cdf72390
institution Directory Open Access Journal
issn 1847-9804
language English
last_indexed 2024-03-09T09:51:58Z
publishDate 2015-05-01
publisher Hindawi - SAGE Publishing
record_format Article
series Nanomaterials and Nanotechnology
spelling doaj.art-7540261b26fc4e509d8b93f3cdf723902023-12-02T00:00:42ZengHindawi - SAGE PublishingNanomaterials and Nanotechnology1847-98042015-05-01515http://dx.doi.org/10.5772/6057748433Electronic, Structural and Vibrational Properties of GaP Diamondoids and Nanocrystals: A Density Functional Theory StudyMudar Ahmed AbdulsattarBahjat B. KadhimHuda M. JawadThe electronic, structural and vibrational properties of gallium phosphide diamondoids and nanocrystals were investigated using density functional theory at PBE/6-31(d) level, which included polarization functions. The energy gap obeyed the quantum confinement size effect with shape fluctuations. The gap converged towards its bulk limit at 2.26 eV. The Ga-P bond lengths of higher diamond‐ oids were found to be distributed around the bulk experi‐ mental value at 2.36 Angstrom. Tetrahedral angles were found around the ideal bulk zincblende value at 109.47, degrees while dihedral angles were distributed around the ideal bulk zincblende values at ±60 and ±180 degree. These findings illustrate that diamondoids are a good represen‐ tative of bulk structure. An analysis of vibrational modes, in terms of reduced masses, force constants and IR intensi‐ ty, was then performed. The size-related change of certain vibrational frequencies of GaP diamondoids was compared with the experimental bulk. Radial breathing mode frequency began from 187 cm-1 for the smallest molecule GaPH6 and decreased with fluctuations, heading to 0 cm-1 as its bulk limit. Longitudinal optical mode began from 187 cm-1 for the smallest molecule and increased with fluctua‐ tions, heading to 376.9 cm-1 (11.3 THz) as its bulk limit. Hydrogen-related vibrations were relatively constant and can therefore be used to identify GaP diamondoids because of their high IR and Raman intensity peaks.http://www.intechopen.com/journals/nanomaterials_and_nanotechnology/electronic-structural-and-vibrational-properties-of-gap-diamondoids-and-nanocrystals-a-density-functDiamondoidsDFTNanocrystals
spellingShingle Mudar Ahmed Abdulsattar
Bahjat B. Kadhim
Huda M. Jawad
Electronic, Structural and Vibrational Properties of GaP Diamondoids and Nanocrystals: A Density Functional Theory Study
Nanomaterials and Nanotechnology
Diamondoids
DFT
Nanocrystals
title Electronic, Structural and Vibrational Properties of GaP Diamondoids and Nanocrystals: A Density Functional Theory Study
title_full Electronic, Structural and Vibrational Properties of GaP Diamondoids and Nanocrystals: A Density Functional Theory Study
title_fullStr Electronic, Structural and Vibrational Properties of GaP Diamondoids and Nanocrystals: A Density Functional Theory Study
title_full_unstemmed Electronic, Structural and Vibrational Properties of GaP Diamondoids and Nanocrystals: A Density Functional Theory Study
title_short Electronic, Structural and Vibrational Properties of GaP Diamondoids and Nanocrystals: A Density Functional Theory Study
title_sort electronic structural and vibrational properties of gap diamondoids and nanocrystals a density functional theory study
topic Diamondoids
DFT
Nanocrystals
url http://www.intechopen.com/journals/nanomaterials_and_nanotechnology/electronic-structural-and-vibrational-properties-of-gap-diamondoids-and-nanocrystals-a-density-funct
work_keys_str_mv AT mudarahmedabdulsattar electronicstructuralandvibrationalpropertiesofgapdiamondoidsandnanocrystalsadensityfunctionaltheorystudy
AT bahjatbkadhim electronicstructuralandvibrationalpropertiesofgapdiamondoidsandnanocrystalsadensityfunctionaltheorystudy
AT hudamjawad electronicstructuralandvibrationalpropertiesofgapdiamondoidsandnanocrystalsadensityfunctionaltheorystudy