{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/20354"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/20354","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Theoretical study of surface related phenomena of BCC transition metals","abstract":"U of I Only","abstract_html":"U of I Only","abstract_has_math":false,"creators":["Xu, Wei"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Materials Engineering","degree_department":null,"school":null,"contributors":["Adams, James B."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-07T12:36:49Z","date_published":"2011-05-07T12:36:49Z","updated_at":"2026-07-22T22:25:15Z","subjects":["Physics, Condensed Matter","Engineering, Materials Science"],"languages":["eng"],"rights":["Copyright 1995 Xu, Wei"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9543777","(UMI)AAI9543777"],"render_values":[{"text":"AAI9543777","href":null,"code":true},{"text":"(UMI)AAI9543777","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/20354","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Adams, James B."]},{"key":"dc:creator","label":"Author","values":["Xu, Wei"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-05-07T12:36:49Z","10000-01-01","1995"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Materials Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Physics, Condensed Matter","Engineering, Materials Science"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 1995 Xu, Wei"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9543777","(UMI)AAI9543777","http://hdl.handle.net/2142/20354"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["U of I Only","Restriction data tranferred 2014-07-01T11:18:57-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","We have carried out a theoretical study of surface related phenomena for three bcc transition metals: tungsten (W), molybdenum (Mo) and vanadium (V), using a newly developed atomic potential, the fourth moment method. The fourth moment method is based on the second, third and fourth moment approximation of tight-binding theory in which three and four body terms are included to describe the partially filled d-bands. This method was fit to twelve bulk properties and the fitting results of these bulk properties are in good agreement with experimental results, except for some phonon modes.","This potential was used to study surface related phenomena. (1) Structure of W(100), Mo(100), V(100), W(110), W(111), W(210), W(211), W(310) and W(321) surfaces. (2) Self-diffusion of W single adatoms on the W(110), (211) and (321) surfaces. The binding site, the activation energy and pre-exponential factor of single W adatom diffusion on these surfaces have been calculated. (3) Small cluster interaction on W(110). The present calculations indicate a strong angular anisotropy and oscillatory behavior of W adatom-adatom interactions on W(110). For long ranges, the interaction is slightly repulsive. (4) Small cluster diffusion on W(110) and (211). We studied the diffusion mechanism of W dimer on those surfaces. The activation energy barrier and pre-exponential factor for W dimer migration have been determined.","In general, most of the calculations are in good agreement with experimental results and ab initio calculations. Some of our results are for systems not previously studied. These calculations have resulted in a more detailed understanding of surface structure and diffusion mechanisms on those surfaces. We found that the inclusion of angular terms does significantly improve the description of the bcc transition metals. This potential is a significant improvement over previous empirical models.","Made available in DSpace on 2011-05-07T12:36:49Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9543777.pdf: 6119541 bytes, checksum: af962e27fbd23f27be68cc021e8c0b52 (MD5) Previous issue date: 1995","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:43:20Z Item is restricted indefinitely.","ETDs are only available to UIUC Users without author permission"]},{"key":"dc:title","label":"Title","values":["Theoretical study of surface related phenomena of BCC transition metals"]}]}],"canonical_facts":{"dc:contributor":["Adams, James B."],"dc:creator":["Xu, Wei"],"dc:date":["2011-05-07T12:36:49Z","10000-01-01","1995"],"dc:description":["U of I Only","Restriction data tranferred 2014-07-01T11:18:57-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","We have carried out a theoretical study of surface related phenomena for three bcc transition metals: tungsten (W), molybdenum (Mo) and vanadium (V), using a newly developed atomic potential, the fourth moment method. The fourth moment method is based on the second, third and fourth moment approximation of tight-binding theory in which three and four body terms are included to describe the partially filled d-bands. This method was fit to twelve bulk properties and the fitting results of these bulk properties are in good agreement with experimental results, except for some phonon modes.","This potential was used to study surface related phenomena. (1) Structure of W(100), Mo(100), V(100), W(110), W(111), W(210), W(211), W(310) and W(321) surfaces. (2) Self-diffusion of W single adatoms on the W(110), (211) and (321) surfaces. The binding site, the activation energy and pre-exponential factor of single W adatom diffusion on these surfaces have been calculated. (3) Small cluster interaction on W(110). The present calculations indicate a strong angular anisotropy and oscillatory behavior of W adatom-adatom interactions on W(110). For long ranges, the interaction is slightly repulsive. (4) Small cluster diffusion on W(110) and (211). We studied the diffusion mechanism of W dimer on those surfaces. The activation energy barrier and pre-exponential factor for W dimer migration have been determined.","In general, most of the calculations are in good agreement with experimental results and ab initio calculations. Some of our results are for systems not previously studied. These calculations have resulted in a more detailed understanding of surface structure and diffusion mechanisms on those surfaces. We found that the inclusion of angular terms does significantly improve the description of the bcc transition metals. This potential is a significant improvement over previous empirical models.","Made available in DSpace on 2011-05-07T12:36:49Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9543777.pdf: 6119541 bytes, checksum: af962e27fbd23f27be68cc021e8c0b52 (MD5) Previous issue date: 1995","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:43:20Z Item is restricted indefinitely.","ETDs are only available to UIUC Users without author permission"],"dc:identifier":["AAI9543777","(UMI)AAI9543777","http://hdl.handle.net/2142/20354"],"dc:language":["eng"],"dc:rights":["Copyright 1995 Xu, Wei"],"dc:subject":["Physics, Condensed Matter","Engineering, Materials Science"],"dc:title":["Theoretical study of surface related phenomena of BCC transition metals"],"dc:type":["text"],"thesis:degree_discipline":["Materials Engineering"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:15Z"}