{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/25581"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/25581","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Superlattice formation in group IV-B transition metal dichalcogenides","abstract":"Electron diffraction studies show that a 2ao x 2co super1attice forms in TiSe2 at low temperature. Strong diffuse scattering is observed above T. An optically active far-infrared lattice mode is observed which c breaks up into several additional modes below the phase transition. In the infrared study, there is a dramatic shift in the Drude edge as well as new absorption peaks at low temperature. These observed phenomena are related to the energy gap which opens up in the band structure below the phase transition temperature. Strong diffuse scattering, which persists down to lOOK, is seen in TiS and HfTe2. No structural transition is observed in these crystals, 2 2but the diffuse scattering may be a precursor to super1attice formation.","abstract_html":"Electron diffraction studies show that a 2ao x 2co super1attice forms in TiSe2 at low temperature. Strong diffuse scattering is observed above T. An optically active far-infrared lattice mode is observed which c breaks up into several additional modes below the phase transition. In the infrared study, there is a dramatic shift in the Drude edge as well as new absorption peaks at low temperature. These observed phenomena are related to the energy gap which opens up in the band structure below the phase transition temperature. Strong diffuse scattering, which persists down to lOOK, is seen in TiS and HfTe2. No structural transition is observed in these crystals, 2 2but the diffuse scattering may be a precursor to super1attice formation.","abstract_has_math":false,"creators":["Woo, Ka-Chiu Eddie"],"institution":null,"degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Physics","degree_department":null,"school":null,"contributors":["Brown, Frederick C."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-06-29T17:44:57Z","date_published":"2011-06-29T17:44:57Z","updated_at":"2026-07-22T22:25:24Z","subjects":["supperlattice formation","group IV-B transition metal dichalocogenides","electron diffraction studies","far-infrared lattice mode"],"languages":["en"],"rights":["1978 Ka-Chiu Eddie Woo"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["355978"],"render_values":[{"text":"355978","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/25581","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Brown, Frederick C."]},{"key":"dc:creator","label":"Author","values":["Woo, Ka-Chiu Eddie"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-06-29T17:44:57Z","10000-01-01","1978"]},{"key":"dc:type","label":"Dc Type","values":["Dissertation / Thesis","text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Physics"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["supperlattice formation","group IV-B transition metal dichalocogenides","electron diffraction studies","far-infrared lattice mode"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["1978 Ka-Chiu Eddie Woo"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["355978","http://hdl.handle.net/2142/25581"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Electron diffraction studies show that a 2ao x 2co super1attice forms in TiSe2 at low temperature. Strong diffuse scattering is observed above T. An optically active far-infrared lattice mode is observed which c breaks up into several additional modes below the phase transition. In the infrared study, there is a dramatic shift in the Drude edge as well as new absorption peaks at low temperature. These observed phenomena are related to the energy gap which opens up in the band structure below the phase transition temperature. Strong diffuse scattering, which persists down to lOOK, is seen in TiS and HfTe2. No structural transition is observed in these crystals, 2 2but the diffuse scattering may be a precursor to super1attice formation.","Submitted by Carolyn Mead (cmead2@illinois.edu) on 2011-06-29T17:44:57Z No. of bitstreams: 1 1978_woo.pdf: 3464032 bytes, checksum: 09c4bb8694b1f863d79fe533693d9165 (MD5)","Made available in DSpace on 2011-06-29T17:44:57Z (GMT). No. of bitstreams: 1 1978_woo.pdf: 3464032 bytes, checksum: 09c4bb8694b1f863d79fe533693d9165 (MD5) Previous issue date: 1978","Restriction data tranferred 2014-07-01T11:32:28-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: Thesis","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Carolyn Mead (cmead2@illinois.edu) on 2011-06-29T17:44:57Z Item is restricted indefinitely.","Thesis","U of I Only"]},{"key":"dc:title","label":"Title","values":["Superlattice formation in group IV-B transition metal dichalcogenides"]}]}],"canonical_facts":{"dc:contributor":["Brown, Frederick C."],"dc:creator":["Woo, Ka-Chiu Eddie"],"dc:date":["2011-06-29T17:44:57Z","10000-01-01","1978"],"dc:description":["Electron diffraction studies show that a 2ao x 2co super1attice forms in TiSe2 at low temperature. Strong diffuse scattering is observed above T. An optically active far-infrared lattice mode is observed which c breaks up into several additional modes below the phase transition. In the infrared study, there is a dramatic shift in the Drude edge as well as new absorption peaks at low temperature. These observed phenomena are related to the energy gap which opens up in the band structure below the phase transition temperature. Strong diffuse scattering, which persists down to lOOK, is seen in TiS and HfTe2. No structural transition is observed in these crystals, 2 2but the diffuse scattering may be a precursor to super1attice formation.","Submitted by Carolyn Mead (cmead2@illinois.edu) on 2011-06-29T17:44:57Z No. of bitstreams: 1 1978_woo.pdf: 3464032 bytes, checksum: 09c4bb8694b1f863d79fe533693d9165 (MD5)","Made available in DSpace on 2011-06-29T17:44:57Z (GMT). No. of bitstreams: 1 1978_woo.pdf: 3464032 bytes, checksum: 09c4bb8694b1f863d79fe533693d9165 (MD5) Previous issue date: 1978","Restriction data tranferred 2014-07-01T11:32:28-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: Thesis","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Carolyn Mead (cmead2@illinois.edu) on 2011-06-29T17:44:57Z Item is restricted indefinitely.","Thesis","U of I Only"],"dc:identifier":["355978","http://hdl.handle.net/2142/25581"],"dc:language":["en"],"dc:rights":["1978 Ka-Chiu Eddie Woo"],"dc:subject":["supperlattice formation","group IV-B transition metal dichalocogenides","electron diffraction studies","far-infrared lattice mode"],"dc:title":["Superlattice formation in group IV-B transition metal dichalcogenides"],"dc:type":["Dissertation / Thesis","text"],"thesis:degree_discipline":["Physics"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."]},"updated_at":"2026-07-22T22:25:24Z"}