Doctoral Dissertations

Abstract

"X-ray diffraction of single crystals has developed dramatically over the last century by combining fundamental theories of light, diffraction, and statistics to generate the complete, geometric structure of molecules. The quality of the resulting X -ray structure data are reported in R₁ < 5%, wR2 < 12% and a goodness of fit value of one. This technique was applied specifically to the evaluation of the spin crossover (SCO) compound [Fe(salpm)₂]BF₄ʺ0.5EtOH and how the molecule's geometry changed during a two-step thermal LS-HS conversion. The crystal structure was measured at 100,175,225, and 296 K to yield final R₁ values of 0.047, 0.054, 0.051, and 0.058, respectively. The coordination bond lengths show the spin transitions occur between 100-175K at one crystallographically unique Fe and between 175-225K at the other Fe site. No strong long range interactions are found, suggesting a gradual spin transition. Reaction ofNi(Nalkyl-sal)₂ complexes with Ni(N0₃)₂ form either nickel dimeric, [Ni₃(Rsal)(N0₃)(MeOH)]₂ or trinuclear complexes, Ni₃(Rsal)₄(N0₃)₂. The binuclear complexes, with orthogonal bridging ligands, show overall ferromagnetic interactions. The crystal structures for Ni₃(Rsal)₄(N0₃)₂ from methyl to benzyl were solved and indicate no steric restriction on formation for the series. The trinuclear compounds form an isosceles triangle of metal atoms with the isopropyl analog showing an overall antiferromagnetic interaction with J=+11.386 and J23=-13.891. Lastly, xanthene spirolactam derivatives were structurally analyzed to determine binding modes for their selective and sensitive (µM) detection of metals Cr³⁺, Fe³⁺, Ni²⁺, Co²⁺ and the nerve gas mimic, dichlorophosphate"--Abstract, page iii.

Advisor(s)

Sinn, Ekkehard

Committee Member(s)

Aronstam, Robert
Stavropoulos, Pericles
Sotiriou-Leventis, Lia
Switzer, Jay A., 1950-

Department(s)

Chemistry

Degree Name

Ph. D. in Chemistry

Publisher

Missouri University of Science and Technology

Publication Date

Spring 2012

Pagination

xi, 155 pages

Note about bibliography

Includes bibliographical references (pages 143-154).

Rights

© 2012 Carla Sue Schmiesing Eribal, All rights reserved.

Document Type

Dissertation - Restricted Access

File Type

text

Language

English

Library of Congress Subject Headings

Iron
Magnetic alloys
Nickel
Spin exchange
X-ray crystallography

Thesis Number

T 10000

Print OCLC #

817724419

Electronic OCLC #

908686483

Link to Catalog Record

Electronic access to the full-text of this document is restricted to Missouri S&T users. Otherwise, request this publication directly from Missouri S&T Library or contact your local library.

http://laurel.lso.missouri.edu/record=b93936576~S5

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