Please use this identifier to cite or link to this item: http://arks.princeton.edu/ark:/88435/dsp017p88cg65g
 Title: Synthesis and Characterization of the Solid Solution Na$$_{2}$$Sn$$_{1-x}$$Ir$$_{x}$$O$$_{3}$$ Authors: Fox, Gary M. Advisors: Cava, Robert J. Department: Chemistry Class Year: 2013 Abstract: Motivated by the search for tin-based compounds with novel physical properties, a revised monoclinic unit cell for the compound Na$$_{2}$$Sn$$_{1-x}$$Ir$$_{x}$$O$$_{3}$$ is presented here. Though previously reported with space group #166, R $$\bar{3}$$m, a Rietveld refinement of neutron diffraction data supports a crystal structure of lower symmetry with space group #15, C2/c. By replacing some or all of the tin with iridium, the synthesis of the previously unreported solid solution Na$$_{2}$$Sn$$_{1-x}$$Ir$$_{x}$$O$$_{3}$$ has been optimized experimentally. As a function of increasing iridium concentration, the lattice parameters contract accordingly. This shift in the lattice parameters generally follows the linear trend predicted by Vegard’s law, though the contraction along the a-axis reaches a minimum at an iridium concentration of ~80%. Measurements of the solid solution’s magnetic susceptibility versus temperature decrease with higher iridium concentration as antiferromagnetic coupling replaces the paramagnetic behavior observed at lower concentrations. A critical concentration of iridium x ≈ 0.92 produces an antiferromagnetic ordering transition at 15.75 K. A second, previously unreported magnetic transition at ~4.5 K is also observed, which corresponds to complex, long-range ordering. Given the intricacies of this system’s structural and magnetic properties, further research on this system is warranted. Extent: 72 pages URI: http://arks.princeton.edu/ark:/88435/dsp017p88cg65g Access Restrictions: Walk-in Access. This thesis can only be viewed on computer terminals at the Mudd Manuscript Library. Type of Material: Princeton University Senior Theses Language: en_US Appears in Collections: Chemistry, 1926-2017