Vibrational characterization of glasses using IR Vibrational characterization of glasses using IR reflectance and Raman scatteringreflectance and Raman scattering

P. Boolchand, University of Cincinnati, P. Boolchand, University of Cincinnati, DMR-DMR-03154910315491

●● Recently, we have synthesized pure AgPORecently, we have synthesized pure AgPO33 glass samples with Tglass samples with Tggs substantially higher s substantially higher than those reported in the literature. AgPOthan those reported in the literature. AgPO3 3 forms a chain-glass consisting of POforms a chain-glass consisting of PO44 tetrahedra (Qtetrahedra (Q22 species in the NMR notation). species in the NMR notation). In Raman and IR, we observe In Raman and IR, we observe symmetric symmetric and and asymmetricasymmetric modes ( modes (redred) of PO) of PO44 units units respectively, and note that they follow the respectively, and note that they follow the exclusion rule. Presence of monomers exclusion rule. Presence of monomers composed of small- and large-rings in addition composed of small- and large-rings in addition to long-chains contributes to the richness of to long-chains contributes to the richness of observed lineshapes. Tobserved lineshapes. Tggs drop remarkably, s drop remarkably, and vibrational features evolve and vibrational features evolve systematically as water is co-doped in AgPOsystematically as water is co-doped in AgPO33 glass.glass.

● ● The IR response was obtained using a The IR response was obtained using a

specular reflectance accessory to an 870 specular reflectance accessory to an 870 bench from ThermoNicolet. Raman scattering bench from ThermoNicolet. Raman scattering was excited in the visible (514 nm) using a was excited in the visible (514 nm) using a dispersive T64000 unit from JY-Horiba.dispersive T64000 unit from JY-Horiba.

Vibrational characterization of glasses using IR Vibrational characterization of glasses using IR reflectance and Raman scattering reflectance and Raman scattering

P. Boolchand, University of Cincinnati, P. Boolchand, University of Cincinnati, DMR-0315491DMR-0315491EducationEducation-- ●●The versatile FTIR (Nicolet Nexus 870) with The versatile FTIR (Nicolet Nexus 870) with

a Raman module (top) is used to illustrate a Raman module (top) is used to illustrate physical principles of IR and Raman physical principles of IR and Raman scattering as vibrational probes of local scattering as vibrational probes of local structures in glasses. The complimentary structures in glasses. The complimentary nature of these probes is demonstrated in nature of these probes is demonstrated in a graduate course (ECECS 810). Group a graduate course (ECECS 810). Group theoretical predictions are tested against theoretical predictions are tested against experiments.experiments.

●● The instrument is also used by graduate The instrument is also used by graduate students of the PI ( bottom) and of faculty students of the PI ( bottom) and of faculty colleagues and of collaborators to colleagues and of collaborators to complete their M.S. and Ph.D. Dissertation complete their M.S. and Ph.D. Dissertation work. work.

Outreach- Outreach- ● ● IR and Raman scattering as non-invasive IR and Raman scattering as non-invasive

and trace analysis probes of materials is and trace analysis probes of materials is illustrated to illustrated to undergraduate and high- undergraduate and high- school students.school students.

●● The instruments are also made available The instruments are also made available to industry desiring characterization of to industry desiring characterization of samples. samples.

Nicolet Nexus 870FT-IR / Raman Si-Bolometer

Continuum IR microscope