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Photodecrease. S pair = 0. S pair =-1. Photoincrease. S pair = 0. S pair =+1. Magnetism of Mixed Prussian Blue Analogs and Low Dimensional Frustated Systems Mark W. Meisel (Physics, University of Florida) DMR-0701400.
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Photodecrease Spair= 0 Spair=-1 Photoincrease Spair= 0 Spair=+1 Magnetism of Mixed Prussian Blue Analogs and Low Dimensional Frustated SystemsMark W. Meisel (Physics, University of Florida)DMR-0701400 The ability to purposefully tune magnetic properties of synthetic materials has motivated progress in the area of molecule-based magnets. Our studies show bulk powders of a Prussian blue analog, NaαNi1-xCox[Fe(CN)6]β·nH2O, possess photoinduced magnetism that can be either positive or negative (as shown at right), depending upon the cobalt fraction x, the applied magnetic field, and the temperature. The underlying mechanism of this phenomena is readily modeled [see (a) and (b)] and, thus, allows the photo-controlled magnetic properties to be designed by a choice of the transition metal ions and their concentrations. These developments are now being extended to thin films and nanoparticles, and the magnetic transition temperatures are being shifted to technologically interesting temperatures near 77 K. D.M. Pajerowski, J.E. Gardner, D.R. Talham, M.W. Meisel, J. Am. Chem. Soc., web publication: August 24, 2009, doi:10.1021/ja9012672. Ni Co Fe (a) (b)
Magnetism of Mixed Prussian Blue Analogs and Low Dimensional Frustated SystemsMark W. Meisel (Physics, University of Florida)DMR-0701400 This interdisciplinary research builds upon our long-standing intramural (UF Physics-Chemistry and NHMFL High-B/T Lab) and international (Centre of Low Temperature Physics, Košice, Slovakia) and extends these links (e.g. High Magnetic Field Lab (HLD), Dresden, Germany). The training of graduate and undergraduate students involves hands-on laboratory experiences and visits to national (e.g. SNS-ORNL and NHMFL) and international facilities and meetings. The PI embraces Outreach Activities and his recent work focuses on K-8 teacher/student experiences involving “matter”. Elements of his work were used by the Florida PROMiSE Progam, and the PI is a developer and faculty participant. Temperature (T) versus Magentic Field (B): phase diagram of a novel two-dimensional magnet Cu(tn)Cl2, see A. Orendáčová et al., arXiv:0906.3181 and to be published. Model of Chemical Reactions: Cookie Sheet & Poker Chips! Meisel leads discussion during Duval (Jacksonville) PROMiSE K-8 Teachers Outreach Program. Other NSF grants providing collaborative support: Daniel R. Talham, UF Chem (DMR-0453362), UF Physics Summer REU Program (DMR-0851707), NHMFL (DMR-0654118). Department of Physics Department of Chemistry Meisel Group “Leatherheads” Summer 2009: (left to right) Carrie Schindler, REU, Univ. Evansville; Elisabeth Knowles, UF grad student; Mark Meisel, PI; Daniel Pajerowski, UF grad student, Nick Lavini, REU, Manhattan College.