Muonium in C₆₀ fullerites : studies of structural and electronic properties

μSR studies of crystalline C₆₀ reveal the existence of two distinct paramagnetic states. The experiments described in this thesis confirm that one is an exohedrally bonded muonium radical, while the other is endohedral muonium with a hyperfine parameter Aμ, close to that of muonium in vacuum. The signal from the muonium-C₆₀ radical -- which is characterized by a small Aμ, (10% of Avacμ) and an anisotropic hyperfine interaction -- is sensitive to the molecular dynamics and is used to study the structural phase transition of solid C₆₀ near 260K. Only endohedral muonium is observed in the alkali-metal-doped fullerites K₄C₆₀, K₆C₆₀, and Rb₆C₆₀. From its coherent spin precession, we find all three to be semiconductors with small gaps on the order of 0.5 eV. Our results conflict with the simple band structure model of doped fullerites indicating that electron-electron correlation effects may be important in determining the electronic structure of these solids.

Name thesis:degree_name

Master of Science - MSc

Level thesis:degree_level

master's

Discipline thesis:degree_discipline

Physics

Grantor dc:publisher

University of British Columbia

Year dc:date

1993

Author dc:creator

• Duty, Timothy Lee

Statement dc:rights

• For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.

Language dc:language

eng

Handle dc:identifier

http://hdl.handle.net/2429/1352

OAI identifier oai:identifier

oai:circle.library.ubc.ca:2429/1352