Temperature dependence of radiative and non-radiative decay in the luminescence of one-dimensional pyridinium lead halide hybrids.

The photoluminescence properties of organic-inorganic pyridinium lead bromide [(pyH)PbBr] and iodide [(pyH)PbI] compounds were investigated as a function of temperature. The inorganic substructure consists of face-sharing chains of PbX octahedra. Diffuse reflectance spectra of the compounds show low energy absorption features consistent with charge transfer transitions from the PbX chains to the pyridinium cations.

Polarizable Anionic Sublattices Can Screen Molecular Dipoles in Noncentrosymmetric Inorganic-Organic Hybrids.

We report the growth and photophysical characterization of two polar hybrid lead halide phases, methylenedianiline lead iodide and bromide, (MDA)PbI and (MDA)PbBr, respectively. The phases crystallize in noncentrosymmetric space group 2, which produces a highly oriented molecular dipole moment that gives rise to second harmonic generation (SHG) upon excitation at 1064 nm. While both compositions are isostructural, the size dependence of the SHG signal suggests that the bromide exhibits a stronger phase-matching response whereas the iodide exhibits a significantly weaker non-phase-matching signal.

Reversible Intercalation of Li Ions in an Earth-Abundant Phyllosilicate Clay.

The phyllosilicate family of clays is an intriguing collection of materials that make ideal models for studying the intercalation of alkali ions due to their layered topology and broadly tunable composition space. In this spirit, we present a hydrothermal method to prepare a layered iron phyllosilicate clay, FeSiO(OH), and an evaluation of its electrochemical performance for the (de)insertion of Li ions. Through careful structural refinement, we determined that this iron clay contains a 2:1 stacking sequence, which is directly analogous to the widely studied mineral montmorillonite, with the crystallites adopting a platelike morphology.

Influence of Dimethyl Sulfoxide on the Structural Topology during Crystallization of PbI.

Hybrid metal-organic halides are an exciting class of materials that offer the opportunity to examine how fundamental aspects of chemical bonding can influence the structural topology. In this work, we describe how solvent adducts of lead halides can influence the crystallization and subsequent annealing of these hybrid phases. While the size and shape of organic molecules are known to govern the final topology of the hybrid, we show that the affinity of solvent molecules for Pb ions may also play a previously underappreciated role.

Four Lead-free Layered Double Perovskites with the = 1 Ruddlesden-Popper Structure.

Herein we report the synthesis, structure, and band gaps of four layered halide double perovskites, i.e., BACuInCl, BAAgInCl, BAAgSbCl, and BAAgSbBr [BA = butylammonium = CH(CH)NH], each of which has the = 1 Ruddlesden-Popper structure.

Postsynthetic Metal Exchange in a Metal-Organic Framework Assembled from Co(III) Diphosphine Pincer Complexes.

A Zr metal-organic framework (MOF) 1-CoCl has been synthesized by solvothermal reaction of ZrCl with a carboxylic acid-functionalized Co-PNP pincer complex H(L-CoCl) ([L-CoCl] = [(2,6-(NHPAr)CH)CoCl], Ar = p-CHCO). The structure of 1-CoCl has been determined by X-ray powder diffraction and exhibits a csq topology that differs from previously reported ftw-net Zr MOFs assembled from related Pd- and Pt-PNP pincer complexes. The Co-PNP pincer species readily demetallate upon reduction of Co to Co, allowing for transmetalation with late second and third row transition metals in both the homogeneous complex and 1-CoCl.