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Stone–Wales defect

April 11, 2024

A Stone–Wales defect is a crystallographic defect that involves the change of connectivity of two π-bonded carbon atoms, leading to their rotation by 90° with respect to the midpoint of their bond.[1] The reaction commonly involves conversion between a naphthalene-like structure into a fulvalene-like structure, that is, two rings that share an edge vs two separate rings that have vertices bonded to each other.

Stone–Wales defect in 2D silica (HBS, middle) and graphene (bottom): model and TEM images.[2]

The reaction occurs on carbon nanotubes, graphene, and similar carbon frameworks, where the four adjacent six-membered rings of a pyrene-like region are changed into two five-membered rings and two seven-membered rings when the bond uniting two of the adjacent rings rotates. In these materials, the rearrangement is thought to have important implications for the thermal,[3] chemical, electrical, and mechanical properties.[4] The rearrangement is an example of a pyracyclene rearrangement.

History edit

The defect is named after Anthony Stone and David J. Wales at the University of Cambridge, who described it in a 1986 paper[5] on the isomerization of fullerenes. However, a similar defect was described much earlier by G. J. Dienes in 1952 in a paper on diffusion mechanisms in graphite[6] and later in 1969 in a paper on defects in graphite by Peter Thrower.[7] For this reason, the term Stone–Thrower–Wales defect is sometimes used.

Structural effects edit

The defects have been imaged using scanning tunneling microscopy[citation needed] and transmission electron microscopy[8] and can be determined using various vibrational spectroscopy techniques.[citation needed]

It has been proposed that the coalescence process of fullerenes or carbon nanotubes may occur through a sequence of such a rearrangements.[citation needed] The defect is thought to be responsible for nanoscale plasticity and the brittle–ductile transitions in carbon nanotubes.[citation needed]

Chemical details edit

The activation energy for the simple atomic motion that gives the bond-rotation apparent in a Stone–Wales defects is fairly high—a barrier of several electronvolts.[4][9] but various processes can create the defects at substantially lower energies than might be expected.[8]

The rearrangement creates a structure with less resonance stabilization among the sp2 atoms involved and higher strain energy in the local structure. As a result, the defect creates a region with greater chemical reactivity, including acting as a nucleophile[citation needed] and creating a preferred site for binding to hydrogen atoms.[10] The high affinity of these defects for hydrogen, coupled with the large surface area of the bulk material, might make these defects an important aspect in the use of carbon nanomaterials for hydrogen storage.[10] Incorporation of defects along a carbon-nanotube network can program a carbon-nanotube circuit to enhance the conductance along a specific path.[citation needed] In this scenario, the defects lead to a charge delocalization, which redirects an incoming electron down a given trajectory.

References edit

  1. ^ Brayfindley, Evangelina; Irace, Erica E.; Castro, Claire; Karney, William L. (2015). "Stone–Wales Rearrangements in Polycyclic Aromatic Hydrocarbons: A Computational Study". J. Org. Chem. 80 (8): 3825–3831. doi:10.1021/acs.joc.5b00066. PMID 25843555.
  2. ^ Björkman, T; Kurasch, S; Lehtinen, O; Kotakoski, J; Yazyev, O. V.; Srivastava, A; Skakalova, V; Smet, J. H.; Kaiser, U; Krasheninnikov, A. V. (2013). "Defects in bilayer silica and graphene: common trends in diverse hexagonal two-dimensional systems". Scientific Reports. 3: 3482. Bibcode:2013NatSR...3E3482B. doi:10.1038/srep03482. PMC 3863822. PMID 24336488.
  3. ^ Zhang, Kaiwang; Stocks, G Malcolm; Zhong, Jianxin (June 2007). "Melting and premelting of carbon nanotubes". Nanotechnology. 18 (28): 285703. Bibcode:2007Nanot..18B5703Z. doi:10.1088/0957-4484/18/28/285703. Retrieved 31 August 2021.
  4. ^ a b Zhou, L. G.; Shi, San-Qiang (2003). "Formation energy of Stone–Wales defects in carbon nanotubes" (PDF). Appl. Phys. Lett. 83 (6): 1222–1225. Bibcode:2003ApPhL..83.1222Z. doi:10.1063/1.1599961. hdl:10397/4230.
  5. ^ Stone, A. J.; Wales, D. J. (1986). "Theoretical studies of icosahedral C60 and some related structures". Chemical Physics Letters. 128 (5–6): 501–503. Bibcode:1986CPL...128..501S. doi:10.1016/0009-2614(86)80661-3.
  6. ^ Dienes, G. J. (1952). "Mechanism for Self‐Diffusion in Graphite". Journal of Applied Physics. 23 (11): 1194–1200. Bibcode:1952JAP....23.1194D. doi:10.1063/1.1702030. hdl:2027/mdp.39015095100155.
  7. ^ Thrower, P.A. (1969). "The study of defects in graphite by transmission electron microscopy". Chemistry and Physics of Carbon. 5: 217–320.
  8. ^ a b Kotakoski, J.; Meyer, J. C.; Kurasch, S.; Santos-Cottin, D.; Kaiser, U.; Krasheninnikov, A. V. (2011). "Stone–Wales-type transformations in carbon nanostructures driven by electron irradiation". Phys. Rev. B. 83 (24): 245420–245433. arXiv:1105.1617. Bibcode:2011PhRvB..83x5420K. doi:10.1103/PhysRevB.83.245420. S2CID 15204799.
  9. ^ Fowler, Patrick W.; Baker, Jon (1992). "Energetics of the Stone–Wales pyracylene transformation". J. Chem. Soc., Perkin Trans. 2 (10): 1665–1666. doi:10.1039/P29920001665.
  10. ^ a b Letardi, Sara; Celino, Massimo; Cleri, Fabrizio; Rosato, Vittorio (2002). "Atomic hydrogen adsorption on a Stone–Wales defect in graphite". Surface Science. 496 (1–2): 33–38. Bibcode:2002SurSc.496...33L. doi:10.1016/S0039-6028(01)01437-6.

External links edit

  •   Media related to Stone-Wales defect at Wikimedia Commons

April 11, 2024
stone, wales, defect, crystallographic, defect, that, involves, change, connectivity, bonded, carbon, atoms, leading, their, rotation, with, respect, midpoint, their, bond, reaction, commonly, involves, conversion, between, naphthalene, like, structure, into, . A Stone Wales defect is a crystallographic defect that involves the change of connectivity of two p bonded carbon atoms leading to their rotation by 90 with respect to the midpoint of their bond 1 The reaction commonly involves conversion between a naphthalene like structure into a fulvalene like structure that is two rings that share an edge vs two separate rings that have vertices bonded to each other Stone Wales defect in 2D silica HBS middle and graphene bottom model and TEM images 2 The reaction occurs on carbon nanotubes graphene and similar carbon frameworks where the four adjacent six membered rings of a pyrene like region are changed into two five membered rings and two seven membered rings when the bond uniting two of the adjacent rings rotates In these materials the rearrangement is thought to have important implications for the thermal 3 chemical electrical and mechanical properties 4 The rearrangement is an example of a pyracyclene rearrangement Contents 1 History 2 Structural effects 3 Chemical details 4 References 5 External linksHistory editThe defect is named after Anthony Stone and David J Wales at the University of Cambridge who described it in a 1986 paper 5 on the isomerization of fullerenes However a similar defect was described much earlier by G J Dienes in 1952 in a paper on diffusion mechanisms in graphite 6 and later in 1969 in a paper on defects in graphite by Peter Thrower 7 For this reason the term Stone Thrower Wales defect is sometimes used Structural effects editThe defects have been imaged using scanning tunneling microscopy citation needed and transmission electron microscopy 8 and can be determined using various vibrational spectroscopy techniques citation needed It has been proposed that the coalescence process of fullerenes or carbon nanotubes may occur through a sequence of such a rearrangements citation needed The defect is thought to be responsible for nanoscale plasticity and the brittle ductile transitions in carbon nanotubes citation needed Chemical details editThe activation energy for the simple atomic motion that gives the bond rotation apparent in a Stone Wales defects is fairly high a barrier of several electronvolts 4 9 but various processes can create the defects at substantially lower energies than might be expected 8 The rearrangement creates a structure with less resonance stabilization among the sp2 atoms involved and higher strain energy in the local structure As a result the defect creates a region with greater chemical reactivity including acting as a nucleophile citation needed and creating a preferred site for binding to hydrogen atoms 10 The high affinity of these defects for hydrogen coupled with the large surface area of the bulk material might make these defects an important aspect in the use of carbon nanomaterials for hydrogen storage 10 Incorporation of defects along a carbon nanotube network can program a carbon nanotube circuit to enhance the conductance along a specific path citation needed In this scenario the defects lead to a charge delocalization which redirects an incoming electron down a given trajectory References edit Brayfindley Evangelina Irace Erica E Castro Claire Karney William L 2015 Stone Wales Rearrangements in Polycyclic Aromatic Hydrocarbons A Computational Study J Org Chem 80 8 3825 3831 doi 10 1021 acs joc 5b00066 PMID 25843555 Bjorkman T Kurasch S Lehtinen O Kotakoski J Yazyev O V Srivastava A Skakalova V Smet J H Kaiser U Krasheninnikov A V 2013 Defects in bilayer silica and graphene common trends in diverse hexagonal two dimensional systems Scientific Reports 3 3482 Bibcode 2013NatSR 3E3482B doi 10 1038 srep03482 PMC 3863822 PMID 24336488 Zhang Kaiwang Stocks G Malcolm Zhong Jianxin June 2007 Melting and premelting of carbon nanotubes Nanotechnology 18 28 285703 Bibcode 2007Nanot 18B5703Z doi 10 1088 0957 4484 18 28 285703 Retrieved 31 August 2021 a b Zhou L G Shi San Qiang 2003 Formation energy of Stone Wales defects in carbon nanotubes PDF Appl Phys Lett 83 6 1222 1225 Bibcode 2003ApPhL 83 1222Z doi 10 1063 1 1599961 hdl 10397 4230 Stone A J Wales D J 1986 Theoretical studies of icosahedral C60 and some related structures Chemical Physics Letters 128 5 6 501 503 Bibcode 1986CPL 128 501S doi 10 1016 0009 2614 86 80661 3 Dienes G J 1952 Mechanism for Self Diffusion in Graphite Journal of Applied Physics 23 11 1194 1200 Bibcode 1952JAP 23 1194D doi 10 1063 1 1702030 hdl 2027 mdp 39015095100155 Thrower P A 1969 The study of defects in graphite by transmission electron microscopy Chemistry and Physics of Carbon 5 217 320 a b Kotakoski J Meyer J C Kurasch S Santos Cottin D Kaiser U Krasheninnikov A V 2011 Stone Wales type transformations in carbon nanostructures driven by electron irradiation Phys Rev B 83 24 245420 245433 arXiv 1105 1617 Bibcode 2011PhRvB 83x5420K doi 10 1103 PhysRevB 83 245420 S2CID 15204799 Fowler Patrick W Baker Jon 1992 Energetics of the Stone Wales pyracylene transformation J Chem Soc Perkin Trans 2 10 1665 1666 doi 10 1039 P29920001665 a b Letardi Sara Celino Massimo Cleri Fabrizio Rosato Vittorio 2002 Atomic hydrogen adsorption on a Stone Wales defect in graphite Surface Science 496 1 2 33 38 Bibcode 2002SurSc 496 33L doi 10 1016 S0039 6028 01 01437 6 External links edit nbsp Media related to Stone Wales defect at Wikimedia Commons Retrieved from https en wikipedia org w index php title Stone Wales defect amp oldid 1056535353, wikipedia, wiki, book, books, library,

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