{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/77423"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/77423","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"An X Ray Study of the Structure of Potassium(1-X)-Rubidium(x)-Carbon(y)","abstract":"The mixed layered compounds K$\\sb{\\rm 1-x}$Rb$\\sb{\\rm x}$C$\\sb8$ and K$\\sb{\\rm 1-x}$Rb$\\sb{\\rm x}$C$\\sb{24}$ represent quasi two-dimensional alloys interleaved by graphite hexagonal planes. We report extensive x-ray scattering investigations of the structural aspects of these compounds.","abstract_html":"The mixed layered compounds K$\\sb{\\rm 1-x}$Rb$\\sb{\\rm x}$C$\\sb8$ and K$\\sb{\\rm 1-x}$Rb$\\sb{\\rm x}$C$\\sb{24}$ represent quasi two-dimensional alloys interleaved by graphite hexagonal planes. We report extensive x-ray scattering investigations of the structural aspects of these compounds.","abstract_has_math":true,"creators":["Chow, Paul C."],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Physics","degree_department":null,"school":null,"contributors":["Zabel, Hartmut"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2015,"date_issued":"2015-05-13T15:42:03Z","date_published":"2015-05-13T15:42:03Z","updated_at":"2026-07-22T22:26:10Z","subjects":["Physics, General"],"languages":["eng"],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["(UMI)AAI8908653"],"render_values":[{"text":"(UMI)AAI8908653","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/77423","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Zabel, Hartmut"]},{"key":"dc:creator","label":"Author","values":["Chow, Paul C."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2015-05-13T15:42:03Z","10000-01-01","1988"]},{"key":"dc:type","label":"Dc Type","values":["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."]},{"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, General"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/77423","(UMI)AAI8908653"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["The mixed layered compounds K$\\sb{\\rm 1-x}$Rb$\\sb{\\rm x}$C$\\sb8$ and K$\\sb{\\rm 1-x}$Rb$\\sb{\\rm x}$C$\\sb{24}$ represent quasi two-dimensional alloys interleaved by graphite hexagonal planes. We report extensive x-ray scattering investigations of the structural aspects of these compounds.","In stage 1 K$\\sb{\\rm 1-x}$Rb$\\sb{\\rm x}$C$\\sb8$, we find that the interlayer separation exhibits a slight deviation from linearity, independent of the graphite material used (pyrolytic graphite or single crystals), with a maximum deviation centered at x = 2/3. In the plane, the mixed alkali layers form a (2 x 2)R0$\\sp{\\rm o}$ superstructure with complete site disorder among the K and Rb metal atoms. Extensive low temperature investigations have not revealed any tendency of the mixed layer to either super-order to phase separate. The stacking sequence is independent of alloy composition and is identical to the stacking sequence in KC$\\sb8$ as well as in RbC$\\sb8$. The carbon-carbon bond length appears not to change with alloy composition. By comparing the diffusion constants from a macroscopic diffusion experiment with self diffusion constants obtained from quasi-elastic neutron scattering data, we found that the substitutional intercalation process must be drastically hindered by a barrier at the perimeter of the sample.","The stage 2 K$\\sb{\\rm 1-x}$Rb$\\sb{\\rm x}$C$\\sb{24}$ (x = 0.52, 0.80) compounds were synthesized for the first time. Below the ordering temperature (T$\\sb{\\rm u}$ = 149 and 159K, respectively) peaks corresponding to a discommensuration domain structure are observed, which correspond to the compositional average of the unmixed compounds. By taking single crystal Laue photographs, we have determined the position and orientation of the peaks near the origin. We propose a simple physical model to interpret the x-ray data. Below a second transition temperature T$\\sb{\\rm L}\\cong$ 100K, the domain structure becomes unstable against a composition modulation.","Made available in DSpace on 2015-05-13T15:42:03Z (GMT). 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We report extensive x-ray scattering investigations of the structural aspects of these compounds.","In stage 1 K$\\sb{\\rm 1-x}$Rb$\\sb{\\rm x}$C$\\sb8$, we find that the interlayer separation exhibits a slight deviation from linearity, independent of the graphite material used (pyrolytic graphite or single crystals), with a maximum deviation centered at x = 2/3. In the plane, the mixed alkali layers form a (2 x 2)R0$\\sp{\\rm o}$ superstructure with complete site disorder among the K and Rb metal atoms. Extensive low temperature investigations have not revealed any tendency of the mixed layer to either super-order to phase separate. The stacking sequence is independent of alloy composition and is identical to the stacking sequence in KC$\\sb8$ as well as in RbC$\\sb8$. The carbon-carbon bond length appears not to change with alloy composition. By comparing the diffusion constants from a macroscopic diffusion experiment with self diffusion constants obtained from quasi-elastic neutron scattering data, we found that the substitutional intercalation process must be drastically hindered by a barrier at the perimeter of the sample.","The stage 2 K$\\sb{\\rm 1-x}$Rb$\\sb{\\rm x}$C$\\sb{24}$ (x = 0.52, 0.80) compounds were synthesized for the first time. Below the ordering temperature (T$\\sb{\\rm u}$ = 149 and 159K, respectively) peaks corresponding to a discommensuration domain structure are observed, which correspond to the compositional average of the unmixed compounds. By taking single crystal Laue photographs, we have determined the position and orientation of the peaks near the origin. We propose a simple physical model to interpret the x-ray data. Below a second transition temperature T$\\sb{\\rm L}\\cong$ 100K, the domain structure becomes unstable against a composition modulation.","Made available in DSpace on 2015-05-13T15:42:03Z (GMT). No. of bitstreams: 2 license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5) 8908653.PDF: 4720380 bytes, checksum: 68fb57e91f34601972e036773df390e3 (MD5) Previous issue date: 1988","Embargo set by: Seth Robbins for item 78634 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","U of I Only","168 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1988."],"dc:identifier":["http://hdl.handle.net/2142/77423","(UMI)AAI8908653"],"dc:language":["eng"],"dc:subject":["Physics, General"],"dc:title":["An X Ray Study of the Structure of Potassium(1-X)-Rubidium(x)-Carbon(y)"],"dc:type":["text"],"thesis:degree_discipline":["Physics"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:26:10Z"}