Nuclear magnetic resonance investigations of structural phase transitions in silicon dioxide cristobalite and tridymite and related phases
Xiao, Yuehui
This item is only available for download by members of the University of Illinois community. Students, faculty, and staff at the U of I may log in with your NetID and password to view the item. If you are trying to access an Illinois-restricted dissertation or thesis, you can request a copy through your library's Inter-Library Loan office or purchase a copy directly from ProQuest.
Permalink
https://hdl.handle.net/2142/21128
Description
Title
Nuclear magnetic resonance investigations of structural phase transitions in silicon dioxide cristobalite and tridymite and related phases
Author(s)
Xiao, Yuehui
Issue Date
1994
Doctoral Committee Chair(s)
Kirkpatrick, R. James
Department of Study
Geology
Discipline
Geology
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
Mineralogy
Chemistry, Inorganic
Physics, Condensed Matter
Language
eng
Abstract
This thesis contributes to the application of nuclear magnetic resonance (NMR) techniques in studying structural phase transitions (SPT's) of the SiO$\sb2$ cristobalite and SiO$\sb2$ and AlPO$\sb4$ tridymite polymorphs. The structural properties and SPT's of these phases have been of mineralogical, physical and industrial interest for decades. However, the microscopic characteristics of the SPT's and the origins of the commonly observed structural disorder in the high temperature phases have been poorly known. NMR techniques call provide important information concerning the temperature variation of the short-range structural parameters through SPT's. Moreover, the dynamical behavior of high temperature phases in the NMR frequency range ($\sim$1-500 MHz) can sometimes be uniquely elucidated by relaxation rate measurements and spectral simulation. The work presented here includes in situ high temperature $\sp{29}$Si, $\sp{31}$P and $\sp{27}$Al NMR results for cristobalite (Chapter II), chemically stabilized $\beta$-cristobalite (Chapter III), various tridymite polymorphs (MC and PO, Chapter IV; MX-1 Chapter V; AlPO$\sb4,$ Chapter VI) and a spin-lattice relaxation investigation of the dynamic properties for the high temperature SiO$\sb2$ and AlPO$\sb4$ tridymite phases (Chapter VII).
Use this login method if you
don't
have an
@illinois.edu
email address.
(Oops, I do have one)
IDEALS migrated to a new platform on June 23, 2022. If you created
your account prior to this date, you will have to reset your password
using the forgot-password link below.
