{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/25535"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/25535","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"The effect of hydrostatic pressure on the ionic conductivity of some crystals with the flourite structure","abstract":"The effect of hydrostatic pressure on the ionic conductivity of CaF2 SrF2 BaF2 CdF2 SrCl2 PbF2 PbCl2 PbBr2 and PbI2 has been studied for pressures up to 0.6 GPa and temperatures up to near the melting point. The activation volumes for extrinsic vacancy motion were obtained from the effect of pressure on the conductivity of doped and oxygen contaminated samples. The formation volumes of intrinsic defects were calculated from measured activation volumes at high temperatures. The defect formation volumes are found to be uniformly small and consis- tent with the dominance of Frenkel defects in all cases except PbCl2 and PbBr2. where large formation volumes were observed. indicating Schottky defects. High pressure phase transitions in PbF2 SrCl2 and PbI2 were observed by the change in sample resistance across the transition. Transition temperature and pressure data are presented for pressures to 0.55 CPa and temperatures to near the melting point in PbIz to 850 K for PbF2 and to 1050K for SrCl2. The transition temperature is observed to increase linearly with increasing pressure at high temperatures for both PbF2 and SrCt2 but considerable hysteresis is observed in the transition at low temperatures. The transition in PbI2 occurs at approximately 0.39 GPa and is observed to be essentially temperature independent. The temperature dependence of the ionic conductivity has also been studied in all of the above materials. Good agreement with published results is obtained except in the cases of PbCl2 and PbBr2. The differences in those two cases are attributed to differences in the fitting procedure used to analyze the data. A large frequency dependence of the measured conductivity at high temperatures (0 ~ lO-3 ohm-1cm-1) is found to exist in all crystals with the fluorite structure. The observed frequency dependence is attributed either to polarization at the electrode interface or to an inherent dielectric response of the material resulting from many-body interactions, or a combination of these two effects.","abstract_html":"The effect of hydrostatic pressure on the ionic conductivity of CaF2 SrF2 BaF2 CdF2 SrCl2 PbF2 PbCl2 PbBr2 and PbI2 has been studied for pressures up to 0.6 GPa and temperatures up to near the melting point. The activation volumes for extrinsic vacancy motion were obtained from the effect of pressure on the conductivity of doped and oxygen contaminated samples. The formation volumes of intrinsic defects were calculated from measured activation volumes at high temperatures. The defect formation volumes are found to be uniformly small and consis- tent with the dominance of Frenkel defects in all cases except PbCl2 and PbBr2. where large formation volumes were observed. indicating Schottky defects. High pressure phase transitions in PbF2 SrCl2 and PbI2 were observed by the change in sample resistance across the transition. Transition temperature and pressure data are presented for pressures to 0.55 CPa and temperatures to near the melting point in PbIz to 850 K for PbF2 and to 1050K for SrCl2. The transition temperature is observed to increase linearly with increasing pressure at high temperatures for both PbF2 and SrCt2 but considerable hysteresis is observed in the transition at low temperatures. The transition in PbI2 occurs at approximately 0.39 GPa and is observed to be essentially temperature independent. The temperature dependence of the ionic conductivity has also been studied in all of the above materials. Good agreement with published results is obtained except in the cases of PbCl2 and PbBr2. The differences in those two cases are attributed to differences in the fitting procedure used to analyze the data. A large frequency dependence of the measured conductivity at high temperatures (0 ~ lO-3 ohm-1cm-1) is found to exist in all crystals with the fluorite structure. The observed frequency dependence is attributed either to polarization at the electrode interface or to an inherent dielectric response of the material resulting from many-body interactions, or a combination of these two effects.","abstract_has_math":false,"creators":["Oberschmidt, James Michael"],"institution":null,"degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Physics","degree_department":null,"school":null,"contributors":["Lazarus, David"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-06-27T16:08:41Z","date_published":"2011-06-27T16:08:41Z","updated_at":"2026-07-22T22:25:24Z","subjects":["hydrostatic pressure","ionic conductivity","crystals","fluoride structure","activation volumes","extrinsic vacancy motion"],"languages":["en"],"rights":["1980 James Michael Oberschmidt"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["437910"],"render_values":[{"text":"437910","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/25535","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Lazarus, David"]},{"key":"dc:creator","label":"Author","values":["Oberschmidt, James Michael"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-06-27T16:08:41Z","10000-01-01","1980"]},{"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":["hydrostatic pressure","ionic conductivity","crystals","fluoride structure","activation volumes","extrinsic vacancy motion"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["1980 James Michael Oberschmidt"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["437910","http://hdl.handle.net/2142/25535"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["The effect of hydrostatic pressure on the ionic conductivity of CaF2 SrF2 BaF2 CdF2 SrCl2 PbF2 PbCl2 PbBr2 and PbI2 has been studied for pressures up to 0.6 GPa and temperatures up to near the melting point. The activation volumes for extrinsic vacancy motion were obtained from the effect of pressure on the conductivity of doped and oxygen contaminated samples. The formation volumes of intrinsic defects were calculated from measured activation volumes at high temperatures. The defect formation volumes are found to be uniformly small and consis- tent with the dominance of Frenkel defects in all cases except PbCl2 and PbBr2. where large formation volumes were observed. indicating Schottky defects. High pressure phase transitions in PbF2 SrCl2 and PbI2 were observed by the change in sample resistance across the transition. Transition temperature and pressure data are presented for pressures to 0.55 CPa and temperatures to near the melting point in PbIz to 850 K for PbF2 and to 1050K for SrCl2. The transition temperature is observed to increase linearly with increasing pressure at high temperatures for both PbF2 and SrCt2 but considerable hysteresis is observed in the transition at low temperatures. The transition in PbI2 occurs at approximately 0.39 GPa and is observed to be essentially temperature independent. The temperature dependence of the ionic conductivity has also been studied in all of the above materials. Good agreement with published results is obtained except in the cases of PbCl2 and PbBr2. The differences in those two cases are attributed to differences in the fitting procedure used to analyze the data. A large frequency dependence of the measured conductivity at high temperatures (0 ~ lO-3 ohm-1cm-1) is found to exist in all crystals with the fluorite structure. The observed frequency dependence is attributed either to polarization at the electrode interface or to an inherent dielectric response of the material resulting from many-body interactions, or a combination of these two effects.","Submitted by Carolyn Mead (cmead2@illinois.edu) on 2011-06-27T16:08:41Z No. of bitstreams: 1 1980_oberschmidt.pdf: 4814999 bytes, checksum: 9d6788444748c580db0b8726c251459a (MD5)","Made available in DSpace on 2011-06-27T16:08:41Z (GMT). No. of bitstreams: 1 1980_oberschmidt.pdf: 4814999 bytes, checksum: 9d6788444748c580db0b8726c251459a (MD5) Previous issue date: 1980","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Carolyn Mead (cmead2@illinois.edu) on 2011-06-27T16:08:41Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:32:24-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: Thesis","Thesis","U of I Only"]},{"key":"dc:title","label":"Title","values":["The effect of hydrostatic pressure on the ionic conductivity of some crystals with the flourite structure"]}]}],"canonical_facts":{"dc:contributor":["Lazarus, David"],"dc:creator":["Oberschmidt, James Michael"],"dc:date":["2011-06-27T16:08:41Z","10000-01-01","1980"],"dc:description":["The effect of hydrostatic pressure on the ionic conductivity of CaF2 SrF2 BaF2 CdF2 SrCl2 PbF2 PbCl2 PbBr2 and PbI2 has been studied for pressures up to 0.6 GPa and temperatures up to near the melting point. The activation volumes for extrinsic vacancy motion were obtained from the effect of pressure on the conductivity of doped and oxygen contaminated samples. The formation volumes of intrinsic defects were calculated from measured activation volumes at high temperatures. The defect formation volumes are found to be uniformly small and consis- tent with the dominance of Frenkel defects in all cases except PbCl2 and PbBr2. where large formation volumes were observed. indicating Schottky defects. High pressure phase transitions in PbF2 SrCl2 and PbI2 were observed by the change in sample resistance across the transition. Transition temperature and pressure data are presented for pressures to 0.55 CPa and temperatures to near the melting point in PbIz to 850 K for PbF2 and to 1050K for SrCl2. The transition temperature is observed to increase linearly with increasing pressure at high temperatures for both PbF2 and SrCt2 but considerable hysteresis is observed in the transition at low temperatures. The transition in PbI2 occurs at approximately 0.39 GPa and is observed to be essentially temperature independent. The temperature dependence of the ionic conductivity has also been studied in all of the above materials. Good agreement with published results is obtained except in the cases of PbCl2 and PbBr2. The differences in those two cases are attributed to differences in the fitting procedure used to analyze the data. A large frequency dependence of the measured conductivity at high temperatures (0 ~ lO-3 ohm-1cm-1) is found to exist in all crystals with the fluorite structure. The observed frequency dependence is attributed either to polarization at the electrode interface or to an inherent dielectric response of the material resulting from many-body interactions, or a combination of these two effects.","Submitted by Carolyn Mead (cmead2@illinois.edu) on 2011-06-27T16:08:41Z No. of bitstreams: 1 1980_oberschmidt.pdf: 4814999 bytes, checksum: 9d6788444748c580db0b8726c251459a (MD5)","Made available in DSpace on 2011-06-27T16:08:41Z (GMT). No. of bitstreams: 1 1980_oberschmidt.pdf: 4814999 bytes, checksum: 9d6788444748c580db0b8726c251459a (MD5) Previous issue date: 1980","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Carolyn Mead (cmead2@illinois.edu) on 2011-06-27T16:08:41Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:32:24-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: Thesis","Thesis","U of I Only"],"dc:identifier":["437910","http://hdl.handle.net/2142/25535"],"dc:language":["en"],"dc:rights":["1980 James Michael Oberschmidt"],"dc:subject":["hydrostatic pressure","ionic conductivity","crystals","fluoride structure","activation volumes","extrinsic vacancy motion"],"dc:title":["The effect of hydrostatic pressure on the ionic conductivity of some crystals with the flourite structure"],"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"}