Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 2 of 2
Full-Text Articles in Physical Sciences and Mathematics
Development And Application Of New Solid-State Models For Low-Energy Vibrations, Lattice Defects, Entropies Of Mixing, And Magnetic Properties, Jacob M. Schliesser
Development And Application Of New Solid-State Models For Low-Energy Vibrations, Lattice Defects, Entropies Of Mixing, And Magnetic Properties, Jacob M. Schliesser
Theses and Dissertations
Low-temperature heat capacity data contain information on the physical properties of materials, and new models continue to be developed to aid in the analysis and interpretation of heat capacity data into physically meaningful properties. This work presents the development of two such models and their application to real material systems. Equations describing low-energy vibrational modes with a gap in the density of states (DOS) have been derived and tested on several material systems with known gaps in the DOS, and the origins of such gaps in the DOS are presented. Lattice vacancies have been shown to produce a two-level system …
From Model Systems To Real Catalysts: Bridging The Pressure And Materials Gaps, Audrey S. Duke
From Model Systems To Real Catalysts: Bridging The Pressure And Materials Gaps, Audrey S. Duke
Theses and Dissertations
For decades a fundamental understanding of heterogeneous catalysts has been pursued for rational catalyst design using model systems under ultrahigh vacuum (UHV) conditions; however, there exist stark differences between the simplified models investigated under UHV and the industrial catalysts used at high pressures. To bridge these gaps, it becomes essential to utilize progressively more complex materials and to correlate their surface structure and activity using incrementally higher pressure techniques. In this work, both model Pt-Re catalysts and powdered metal-organic frameworks (MOFs) were studied using a suite of traditional UHV surface science techniques in addition to ambient pressure X-ray photoelectron spectroscopy …