Identifier

etd-07202011-163444

Degree

Doctor of Philosophy (PhD)

Department

Chemistry

Document Type

Dissertation

Abstract

The structural solution and physical property characterization of several Ln-T-Al/Ga and Ln-T-Al-Si contain phases, which include Ln(Cu,Al)12 (Ln = Y, Ce, Pr, Sm, and Yb), Ln(Ag,Al,Si)2 (Ln = Ce and Gd), LnCu2(Al,Si)5 (Ln = La and Ce), Ln(Cu,Al,Ga)13-x (Ln = La, Ce, Pr, and Eu), α and β LnNiGa4 (α Ln = Y and Gd – Yb; β Ln = (Tb – Er)), and Ln4FeGa12 (Ln = Tb – Er) will be presented in this work with an emphasis on crystal growth. The systems cover a large breadth of phase space and serve to illustrate the new and rich chemistry and physics that remain, to this day, to be discovered in these phase spaces. Additionally, these phases range in complexity, to the eloquently simple open network found in Ln(Ag,Al,Si)2 to the more complex 3 dimensional polyhedral environments of Ln(Cu,Al)12 (Ln = Y, Ce, Pr, Sm, and Yb) or Ln(Cu,Al,Ga)13-x. In all cases these phases were discovered from systematic progressions throughout the periodic table and can all trace their roots to one phase, CePdGa6. Chapter 1 of this document describes the logic and motivation behind the exploration of the Ln-Cu-Al phase space and alludes to some serendipitous discoveries. Additionally, it treats the issues of a failing materials science effort in America as recently outline in a recent National Academies of Science document: Frontiers in Crystalline Matter: From Discovery to Technology. Time is taken to discuss what is needed to once again assume a predominate role in these ventures and how our group aligns itself with the proposed directives Chapters 2 – 5 provide in-depth discussion of selected phases as it relates to their respective crystalline growth, structure, magnetic, and transport properties.

Date

2011

Document Availability at the Time of Submission

Secure the entire work for patent and/or proprietary purposes for a period of one year. Student has submitted appropriate documentation which states: During this period the copyright owner also agrees not to exercise her/his ownership rights, including public use in works, without prior authorization from LSU. At the end of the one year period, either we or LSU may request an automatic extension for one additional year. At the end of the one year secure period (or its extension, if such is requested), the work will be released for access worldwide.

Committee Chair

Chan, Julia

Included in

Chemistry Commons

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