© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim Phys. Status Solidi RRL, 1–6 (2016) / DOI 10.1002/pssr.201600175 www.pss-rapid.com pss Efficient synthesis and tailoring of magnetic and dielectric properties of Pb-free perovskite-like ABX 3 metal-organic frameworks Nandita Abhyankar 1 , Minseong Lee 2 , Megan Foley 1 , Eun Sang Choi 2 , Geoffrey Strouse *, 1 , Harold W. Kroto 1 , and Naresh S. Dalal **, 1, 2 1 Department of Chemistry and Biochemistry, Florida State University, Tallahassee, 32306-4390, USA 2 National High Magnetic Field Laboratory, 1800 E. Paul Dirac Drive, Tallahassee, 32310, USA Received 15 June 2016, revised 10 July 2016, accepted 11 July 2016 Published online 18 July 2016 Keywords Multiferroics, metal-organic frameworks, hybrid perovskites, microwave-assisted synthesis ** Corresponding author: e-mail strouse@chem.fsu.edu ** e-mail dalal@chem.fsu.edu © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim 1 Introduction Multiferroics, or single-phase materi- als that simultaneously exhibit magnetic and electric order- ing, are an area of intense research interest because of their rarity as well as potential applications in information storage and manipulation. Perovskite-like (ABX 3 ) metal– organic frameworks (MOFs) are potential Pb-free alterna- tives to the widely used lead zirconate titanate (PZT) fam- ily of dielectrics [1–3]. Dimethylammonium metal for- mates, with the general formula [(CH 3 ) 2 NH 2 ]M(HCOO) 3 (M = Mn 2+ , Fe 2+ , Co 2+ , Ni 2+ , Zn 2+ ), were first reported in 2004 by Wang et al. [1], who described the soft ferromag- netic properties of these MOFs containing Mn 2+ , Co 2+ , and Ni 2+ . In 2008, the Zn-analogue was shown to display ferro- electric ordering based on an order-disorder phase transi- tion [2]. In 2009, these materials were shown to be mul- tiferroic for the case of MOFs containing paramagnetic ions. They display ferroelectric phase transitions with Curie temperatures in the range 160–185 K, and become canted ferromagnets below critical temperatures ranging from 8–35 K, making them the first and one of the most studied family of hybrid multiferroic MOFs [3]. A number of variations of the perovskite-like ABX 3 motif have since been obtained by varying the organic A-site cation ion (which has been replaced by guanidinium, ammonium, formamidinium, etc.); the B-site metal ion; as well as the anionic linker [4–18]. These compositional variations re- sult in a variety of properties, including glassy behavior [10], akin to that shown by the PZT family. More recently, Perovskite-like metal-organic frameworks (MOFs) are hy- brid materials of high interest for their potential in infor- mation storage technology, as Pb-free substitutes for the widely used lead zirconate titanate (PZT) family of mul- tiferroics. We report here a new, microwave-assisted method of synthesis for perovskite-like MOFs, which ex- ploits the advantages of rapid and volumetric heating by microwaves in order to achieve synthesis within minutes, compared to days required by previously reported meth- ods. The preliminary results demonstrate a broad control over the size and morphology of the products, by minor changes in the reaction conditions. An investigation of the effects of size and morphology on the magnetic and di- electric properties is presented here.