High-Temperature Switchable Dielectric of an Organic–Inorganic Hybrid Metal Halide with Four-fold Cross-Linking Inorganic Anion Spiral Chains

The
understanding of structure–property relationship and
exploration of novel physical properties are current research topics
of molecular switchable dielectric materials. In this paper, an organic
metal halide {[ClCH2CH2(OH)­CH2N­(CH3)3]­[PbBr3], PbBr2-3-Cl} was obtained by the reaction of 3-chloro-2-hydroxypropyltrimethyl
ammonium chloride and lead bromide in HBr aqueous solution. The structural
analysis reveals that PbBr2-3-Cl consists of an organic
ammonium cation and a four-fold cross-linking spiral inorganic anion
chain, in which the Pb atom is five-coordinated with Br atoms adopting
a square-pyramidal geometry, which is further connected with four
neighboring square-pyramids by sharing four Br atoms at the vertices
of the square-pyramid bottom. PbBr2-3-Cl can be used
as a dielectric switch at a very high temperature (435 K), and a semiconductor
and broadband red fluorescent material.