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A new hybrid perovskite of [FCH2CH2NH3][Mn(HCOO)3] has been successfully prepared by utilizing the ammonium of FCH2CH2NH3+, and it is the first example incorporating F‐substituted ammonium in the class of ammonium metal formate framework. The compound crystallizes in polar, orthorhombic space group Pna21, and the cell parameters are a=8.5901(3)–8.7158(6), b=8.4613(3)–8.5216(6), c=12.4837(4)–12.6106(9) Å and V=907.36(5)–936.6(1) Å3 from 80 K up to 410 K just before the decomposition, showing positive thermal expansions in all directions and no structural phase transition in the temperature region. The FCH2CH2NH3+ cation in the cavity of the NaCl‐like Mn‐formate framework adopts N−C−C−F gauche conformation, and its NH3+ and F ends are anchored to the anionic framework by N−H⋅⋅⋅O and C−H⋅⋅⋅F H‐bonds. The large dislocation of the NH3+ end from the anionic framework, about 1.4 Å, results in an estimated high electric polarization about 10 μCcm−2 for the polar structure. The material is also a spin‐canted antiferromagnet with the Néel temperature of 8.3 K. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid perovskites (OIHPs) have gained tremendous interest for their rich functional properties. However, the coexistence of more than one of ferroelectricity, ferromagnetism and ferroelasticity has been rarely found in OIHPs. Herein, we report a two‐dimensional Cr2+‐based OIHP, [3,3‐difluorocyclobutylammonium]2CrCl4 ([DFCBA]2CrCl4), which shows both ferroelectricity and ferromagnetism. It undergoes a 4/mmmFm type ferroelectric phase transition at a temperature as high as 387 K and shows multiaxial ferroelectricity with a saturate polarization of 2.1 μC cm−2. It acts as a soft ferromagnet with a Curie temperature of 32.6 K. This work throws light on the exploration of OIHPs with the coexistence of ferroelectricity and ferromagnetism for applications in future multifunctional smart devices. [ABSTRACT FROM AUTHOR]

Two iso-structural hybrid perovskites of [(CH3)2SO][RE(HCOO)3] for RE3+ = Lu3+ and Y3+ are polar and possess neutral rare earth formate frameworks incorporating dimethyl sulfoxide locating in the framework cavities and coordinating to the RE3+ ions. The materials display reversible phase transitions at 172 K and 138 K for Lu and Y, respectively. The phase transitions are driven by the transformations of weak C–H⋯O interactions and the gradual twists of the constituents in low temperature, which control the order–disorder states of dimethyl sulfoxide and account for different anisotropic thermal expansion behaviors for the two phases and the characters of dielectric responses. [ABSTRACT FROM AUTHOR]

Structural, magnetic, and transport properties of polycrystalline La[sub 0.7]Ca[sub 0.3]Mn[sub 1-x]Sc[sub x]O[sub 3] have been experimentally investigated. Single-phase samples are obtained in the range 0≤x≤0.25 by the soft chemical synthesis route. The substitution of Sc[sup 3+] at the Mn site results in reductions in the Curie temperature T[sub c] and in the magnetic moment per Mn ion. The T[sub c] transition temperature becomes broader with x, and the magnetic spontaneous state has changed into a cluster glass state for the sample of x=0.1. In addition, great enhancement in resistance and magnetoresistance effect is observed in the Sc-doped samples. In our case the notable doping effects can be mainly ascribed to the variation in the Mn[sup 3+]–O[sup 2-]–Mn[sup 4+] network and to the magnetic disorder caused by the presence of the large and nonmagnetic Sc[sup 3+] ions in the Mn sublattice. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A hybrid layered perovskite compound of [NH4Cl]2[Ni(HCOO)2(NH3)2] consists of alternatively stacked perovskite layers of [Ni(HCOO)2(NH3)2] and CsCl-type slabs of [(NH3)2(NH4Cl)2]. The material undergoes a ferro- to ferro-electric transition around 110 K, from a high temperature, high polarized phase to a low temperature, low polarized one via an intermediate incommensurate phase and then a para- to antiferro-magnetic transition at 25 K. It displays significant anisotropic dielectric and magnetic responses, and both electric and magnetic polarizations turn from the direction perpendicular to the layers to the direction parallel to the layers during the transitions. [ABSTRACT FROM AUTHOR]

An abnormal magnetic/transport phase diagram in La(sub 0.7-x)Lu(sub x)Sr(sub 0.3)MnO(sub 3) is presented. The magnetic inhomogeneity caused by different local distortion of the Lattice around La(super 3+) and Lu(super 3+) ions is responsible for the magnetic/transport abnormality.