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oai:www.ideals.illinois.edu:2142/70345 2023-07-11 col_2142_5131 col_2142_14789 com_2142_5130 com_2142_14788 com_2142_8903

283 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1986. http://hdl.handle.net/2142/70345 (UMI)AAI8701503 Chemistry, Organic Hall, Robert Cargill 2014-12-15T23:18:50Z 2014-12-15T23:18:50Z 10000-01-01 1986 1986 Crystalline organic materials possessing a polar axis have potential applications in information processing and communications fields. Previous work suggests that crystalline naphthazarin (5,8- The case of 12 is interesting because it undergoes a single crys- tal to single crystal phase change. X-ray diffraction of transformed individual crystals show retained crystallinity. dihydroxy-1,4-naphthoquinone) undergoes a rapid tautomeric exchange between 1a and 1b at room temperature. (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI) Upon cooling below 110(DEGREES)K, one form of naphthazarin undergoes a reversible centrosymmetric to noncentrosymmetric phase transition. This thesis reports the structures and solid state chemistry of several quinizarins. Thermally induced solid state transitions have been identified in quinizarin 2 as well as the 2,3-dichloro and 2,3-dimethyl quinizarins 11 and 12. These transitions have been characterized by differential thermal analysis, X-ray powder diffraction, FTIR spectroscopy, and laser second harmonic generation (SHG). X-ray crystal structures have been determined for two forms of 11 and one form of 12. Other quinizarins, naphthazarins, and naphthazarin esters have also been investigated in the solid state, and in several cases X-ray crystal structures have been determined. The transition of 11 is unusual in that it involves a non-polar to polar phase change upon heating. The transition of 11 was charac- terized by the development of laser frequency doubling while heating a powdered sample. The powder SHG efficiency of the high tempera- ture form of 11 is more than twice that of urea (a common SHG standard). Made available in DSpace on 2014-12-15T23:18:50Z (GMT). No. of bitstreams: 1 8701503.pdf: 7292014 bytes, checksum: f29f94136fef8066f389eac9aed7daa8 (MD5) Previous issue date: 1986 Embargo set by: Seth Robbins for item 70511 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs U of I Only Solid-State Chemistry of Quinizarins and Naphthazarins text Chemistry Chemistry University of Illinois at Urbana-Champaign Dissertation Ph.D.