LnBSb2O8 (Ln = Sm, Eu, Gd, Tb): A Series of Lanthanide Boroantimonates with Unusual 3D Anionic Structures

New antimony fluorooxoborates with strong birefringence and unprecedented structural characterisation

Fluorooxoborates constitute a rich source of optical crystals due to their structural diversity and excellent performance. Antimony fluorooxoborates with stereochemically active lone pairs of electrons still have not been found, although the first antimony borate was discovered several years ago. In this study, we have achieved the successful synthesis of the first antimony(III) fluorooxoborate with an unprecedented [B2O4F]∞ chain, namely SbB2O4F. Remarkably, SbB2O4F shows strong birefringence (0.171@1064 nm) and short UV cutoff edges (about 220 nm) according to calculations. The birefringence of SbB2O4F mainly originates from the highly distorted [SbO4] groups.

Cd4REO(BO3)3 (RE = Sm, Eu, Tb): Three new cadmium-rare earth-oxyborates with both good NLO and luminescent properties

Three nonlinear optical materials Cd4REO(BO3)3(RE = Sm, Eu, Tb) have been synthesized through high-temperature solid-state reactions. In their crystal structures, Cd(1)O8 and Cd(2)O6 polyhedra are interconnected via sharing edges and...

Centrosymmetric Rb[Te2O4(OH)5] and noncentrosymmetric K2[Te3O8(OH)4]: metal tellurates with corner and edge-sharing (Te4O18)12- anion group

New nonlinear optical (NLO) crystals have become urgent need for extending laser wavelengths. By cation substitution between alkali metal (K+, Rb+), anion group arrangement transition were realized, and centrosymmetric Rb[Te2O4(OH)5]...

An antimony(iii) borate with large birefringence exhibiting unwonted [B5O11] fundamental building blocks and dimeric [Sb2O6] clusters

By combining π-conjugated [B₃O₆] groups and Sb³⁺ cations with SCALP, we successfully obtained the second antimony(iii) borate SbB₅O₉ with a large birefringence (0.151 @ 1064 nm), which exhibits unwonted [B₅O₁₁] FBBs and dimeric [Sb₂O₆] clusters.

RE(SO4)[B(OH)4](H2O), RE(SO4)[B(OH)4](H2O)2, and RE(SO4)[B(OH)4](H2O)·H2O: Rare-Earth Borate-Sulfates Featuring Three Types of Layered Structures

Using hydrothermal reactions, three series of rare-earth borate-sulfates, namely, RE(SO₄)[B(OH)₄](H₂O) (RE = La (1), Sm (2), Eu (3)), RE(SO₄)[B(OH)₄](H₂O)₂ (RE = Pr (4), Nd (5), Sm (6), Eu (7), Gd (8)), and RE(SO₄)[B(OH)₄](H₂O)·H₂O (RE = Tb (9), Dy (10), Ho (11), Er (12), Tm (13), Yb (14), Lu (15), Y (16)), have been synthesized, which represent the first rare-earth borate-sulfate mixed-anion compounds. All these compounds possess the same fundamental building anionic units of SO₄ and B(OH)₄ tetrahedra; however, they exhibit three different types of two-dimensional (2D) layered structures composed of 1D RE-B-O and RE-S-O chains. The rare-earth borate chains are similar in all compounds, while the rare-earth sulfate chains differ in each type of compound due to the various coordination modes of sulfate groups. On the basis of the measured UV-vis diffuse reflectance spectra, the optical band gaps of compounds 2, 3, 6, and 7 are estimated to be 4.66, 4.53, 4.62, and 4.50 eV, respectively. Luminescence studies show that compounds 2, 3, 6, and 7 exhibit strong emission in the orange or red regions. Furthermore, thermal analysis and magnetic susceptibility measurements for these four representative compounds have also been performed.

Simultaneous structure and luminescence property control of barium carbonate nanocrystals through small amount of lanthanide doping

Rare earth doping has been widely applied in many functional nanomaterials with desirable properties and functions, which would have a significant effect on the growth process of the materials. However, the controlling strategy is limited into high concentration of lanthanide doping, which produces concentration quenching of the lanthanide ion luminescence with an increase in the Ln³⁺ concentration, resulting in lowering the fluorescence quantum yield of lanthanide ion. Herein, for the first time, we demonstrate simultaneous control of the structures and luminescence properties of BaCO₃ nanocrystals via a small amount of Tb³⁺ doping strategy. In fact, Tb³⁺ would partially occupy Ba²⁺ sites, resulting in the changes to the structures of the BaCO₃ nanocrystals, which is primarily determined by charge modulation, including the contributions from the surfaces of crystal nuclei and building blocks. These structurally modified nanocrystals exhibit tunable luminescence properties, thus emerging as potential candidates for photonic devices such as light-emitting diodes and color displays.