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Vibrational characterization of glasses using IR reflectance and Raman scattering P. Boolchand, University of Cincinnati, DMR- 0315491.
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Vibrational characterization of glasses using IR reflectance and Raman scattering P. Boolchand, University of Cincinnati, DMR-0315491 ●Recently, we have synthesized pure AgPO3 glass samples with Tgs substantially higher than those reported in the literature. AgPO3 forms a chain-glass consisting of PO4 tetrahedra (Q2 species in the NMR notation). In Raman and IR, we observe symmetric and asymmetric modes (red) of PO4 units respectively, and note that they follow the exclusion rule. Presence of monomers composed of small- and large-rings in addition to long-chains contributes to the richness of observed lineshapes. Tgs drop remarkably, and vibrational features evolve systematically as water is co-doped in AgPO3 glass. ● The IR response was obtained using a specular reflectance accessory to an 870 bench from ThermoNicolet. Raman scattering was excited in the visible (514 nm) using a dispersive T64000 unit from JY-Horiba.
Continuum IR microscope Nicolet Nexus 870 FT-IR / Raman Si-Bolometer Vibrational characterization of glasses using IR reflectance and Raman scattering P. Boolchand, University of Cincinnati, DMR-0315491 Education- ●The versatile FTIR (Nicolet Nexus 870) with a Raman module (top) is used to illustrate physical principles of IR and Raman scattering as vibrational probes of local structures in glasses. The complimentary nature of these probes is demonstrated in a graduate course (ECECS 810). Group theoretical predictions are tested against experiments. ● The instrument is also used by graduate students of the PI ( bottom) and of faculty colleagues and of collaborators to complete their M.S. and Ph.D. Dissertation work. Outreach- ● IR and Raman scattering as non-invasive and trace analysis probes of materials is illustrated to undergraduate and high- school students. ● The instruments are also made available to industry desiring characterization of samples.