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DF: Fachverband Dielektrische Festkörper

DF 20: Focus Session: Organic ferroelectrics

DF 20.1: Hauptvortrag

Donnerstag, 14. März 2013, 09:30–10:10, H11

Organic Perovskites : Intriguing Magnetic Ferroelectrics — •Naresh Dalal — Florida State University, Tallahassee, FL 32310, USAA

In an effort to synthesize lead-free perovskite ferroelectrics, we have prepared a new class of metal-organic lattices with a perovskite (ABX3) achitecture[1,2]These are compounds using early transition metals as the A-site, dimethyl amine ( or other homologues) as the B site and the O's of a carboxylic acid as the X sites. The new perovskites exhibit order-disorder as well as displacive phase transitions,with ferroelectric or antiferroelectric behaviors. They can become ferro- or antiferromagnets if magnetic ions such as Fe, Cu (II) utilize magnetic ions such as Cu(II) or Mn (II) ions or their combinations thereof . We will present polarization and NMR, specific heat and NMR relaxation data that show these materials to be glasses. The talk will present experimental as well as theoretical data showing these materials exotic ground states.

[1]Jain, Ramachandran, Clark, Zhou, Dalal, Kroto, Cheetham J. Am. Chem. Soc. 2009, 131, 13625-13627. [2]Besara, Jain, Dalal, Kuhns, Reyes, Kroto, Cheetham. Proc. Nat. Acad. Sci,, USA, 2011, 108, 6828-6832.