A Member of Fluorooxoborates: Li₂Na_0.9K_0.1B₅O₈F₂ with the Fundamental Building Block B₅O₁₀F₂ and a Short Cutoff Edge

A new member of fluorooxoborates, Li₂Na_0.9K_0.1B₅O₈F₂, was obtained in the sealed system, and single-crystal X-ray diffraction was used to determine its structure. It contains a three-dimensional framework stacking of [B₅O₈F₂]^3– layers extending into the <i>ac</i> plane. Detailed structural comparisons among all of the fluorine-containing alkali-metal borates suggest that the [B₅O₈F₂]^3– layer composed of the new fundamental building blocks B₅O₁₀F₂ represents a new structure type of fluorooxoborate. The IR spectrum verifies its structural validity. The deep-ultraviolet spectral measurement shows that it has no obvious absorption in the range of 180–300 nm, and its cutoff edge is under 180 nm. In addition, theoretical calculations were done to help us understand its electronic structure and optical properties

Effect of the [Ba₂BO₃F]_∞ Layer on the Band Gap: Synthesis, Characterization, and Theoretical Studies of BaZn₂B₂O₆·<i>n</i>Ba₂BO₃F (<i>n</i> = 0, 1, 2)

Two new zincoborate fluorides with the common formula BaZn₂B₂O₆·<i>n</i>Ba₂BO₃F (<i>n</i> = 1, 2) have been successfully synthesized for the relationship study between the band gaps and crystal structures in zinc-containing borate fluorides. Ba₃Zn₂B₃O₉F with <i>n</i> = 1 in the common formula belongs to the orthorhombic space group <i>Pnma</i> (No. 20), and Ba₅Zn₂B₄O₁₂F₂ with <i>n</i> = 2 in the common formula crystallizes in the monoclinic space group <i>C</i>2/<i>c</i> (No. 62). They can both be seen as compounds with the <i>n</i>[Ba₂BO₃F]_∞ (<i>n</i> = 1 or 2) layer inserted in the structure of BaZn₂B₂O₆. UV–vis–near-IR diffuse-reflectance spectra show that the band gaps of BaZn₂B₂O₆·<i>n</i>Ba₂BO₃F (<i>n</i> = 0, 1, 2) gradually increase with more [Ba₂BO₃F]_∞ layers inserted. The first-principles calculation indicates that the inserted n­[Ba₂BO₃F]_∞ layers play a positive effect in increasing the band gaps of zincoborate fluorides. Furthermore, the IR spectra, thermal behaviors, and refractive indices of these compounds are also studied

Effect of the [Ba₂BO₃F]_∞ Layer on the Band Gap: Synthesis, Characterization, and Theoretical Studies of BaZn₂B₂O₆·<i>n</i>Ba₂BO₃F (<i>n</i> = 0, 1, 2)

Two new zincoborate fluorides with the common formula BaZn₂B₂O₆·<i>n</i>Ba₂BO₃F (<i>n</i> = 1, 2) have been successfully synthesized for the relationship study between the band gaps and crystal structures in zinc-containing borate fluorides. Ba₃Zn₂B₃O₉F with <i>n</i> = 1 in the common formula belongs to the orthorhombic space group <i>Pnma</i> (No. 20), and Ba₅Zn₂B₄O₁₂F₂ with <i>n</i> = 2 in the common formula crystallizes in the monoclinic space group <i>C</i>2/<i>c</i> (No. 62). They can both be seen as compounds with the <i>n</i>[Ba₂BO₃F]_∞ (<i>n</i> = 1 or 2) layer inserted in the structure of BaZn₂B₂O₆. UV–vis–near-IR diffuse-reflectance spectra show that the band gaps of BaZn₂B₂O₆·<i>n</i>Ba₂BO₃F (<i>n</i> = 0, 1, 2) gradually increase with more [Ba₂BO₃F]_∞ layers inserted. The first-principles calculation indicates that the inserted n­[Ba₂BO₃F]_∞ layers play a positive effect in increasing the band gaps of zincoborate fluorides. Furthermore, the IR spectra, thermal behaviors, and refractive indices of these compounds are also studied

Borate Fluoride and Fluoroborate in Alkali-Metal Borate Prepared by an Open High-Temperature Solution Method

By incorporation of the largest-electronegativity F atoms into borate, two novel halogen-containing borates, Li₆RbB₂O₆F and K₃B₃O₃F₆, have been synthesized. Interestingly, Li₆RbB₂O₆F is the first borate fluoride in alkali-metal borate. Meanwhile, K₃B₃O₃F₆ appears to be the first confirmed alkali-metal fluoroborate crystal grown by a high-temperature solution in air

Borate Fluoride and Fluoroborate in Alkali-Metal Borate Prepared by an Open High-Temperature Solution Method

By incorporation of the largest-electronegativity F atoms into borate, two novel halogen-containing borates, Li₆RbB₂O₆F and K₃B₃O₃F₆, have been synthesized. Interestingly, Li₆RbB₂O₆F is the first borate fluoride in alkali-metal borate. Meanwhile, K₃B₃O₃F₆ appears to be the first confirmed alkali-metal fluoroborate crystal grown by a high-temperature solution in air

Borate Fluoride and Fluoroborate in Alkali-Metal Borate Prepared by an Open High-Temperature Solution Method

By incorporation of the largest-electronegativity F atoms into borate, two novel halogen-containing borates, Li₆RbB₂O₆F and K₃B₃O₃F₆, have been synthesized. Interestingly, Li₆RbB₂O₆F is the first borate fluoride in alkali-metal borate. Meanwhile, K₃B₃O₃F₆ appears to be the first confirmed alkali-metal fluoroborate crystal grown by a high-temperature solution in air

Application of the Dimensional Reduction Formalism to Pb₁₂[Li₂(P₂O₇)₂(P₄O₁₃)₂](P₄O₁₃): a Phosphate Containing Three Types of Isolated P–O Groups

A new phosphate, Pb₁₂[Li₂(P₂O₇)₂(P₄O₁₃)₂]­(P₄O₁₃), containing three types of isolated polyphosphate anionic groups [P₂O₇], and two types of [P₄O₁₃] has been successfully synthesized by using Li₂O as dimensional reduction agent to dismantle Pb₃P₄O₁₃. The isolation of [P₂O₇] and two types of [P₄O₁₃] with different symmetries in the title compound mainly benefits from the large number and flexible coordination of the Pb²⁺ cations

A₃Sr₂P₇O₂₁ (A = Rb, Cs): Two Polyphosphates Based on Different Types of P–O Chains and Ring Structures

Two polyphosphates containing two types of polymerization of the [PO₄] groups, Rb₃Sr₂P₇O₂₁ and Cs₃Sr₂P₇O₂₁, were grown through a spontaneous nucleation method. Single-crystal X-ray diffraction data were collected in order to determine their structures. Interestingly, Rb₃Sr₂P₇O₂₁ is the first example of two kinds of [PO₃]_∞ linear chains coexisting in one phosphate structure. However, in the structure of Cs₃Sr₂P₇O₂₁, the isolated [P₄O₁₂] ring and the 1D [PO₃]_∞ chain can be observed, which is also rare in phosphates. After careful structural analysis, the alkali-metal cations have an effect on the polymerization of the [PO₄] groups and make Rb₃Sr₂P₇O₂₁ and Cs₃Sr₂P₇O₂₁ crystallize in different space groups. What is more, IR spectra, UV–vis–NIR diffuse reflectance spectroscopy data, and first-principles theoretical calculations were adopted to determine the optical properties and the structure–properties relationship of the compounds

Application of the Dimensional Reduction Formalism to Pb₁₂[Li₂(P₂O₇)₂(P₄O₁₃)₂](P₄O₁₃): a Phosphate Containing Three Types of Isolated P–O Groups

A new phosphate, Pb₁₂[Li₂(P₂O₇)₂(P₄O₁₃)₂]­(P₄O₁₃), containing three types of isolated polyphosphate anionic groups [P₂O₇], and two types of [P₄O₁₃] has been successfully synthesized by using Li₂O as dimensional reduction agent to dismantle Pb₃P₄O₁₃. The isolation of [P₂O₇] and two types of [P₄O₁₃] with different symmetries in the title compound mainly benefits from the large number and flexible coordination of the Pb²⁺ cations

Special _∞¹[OPb₂] Chains and _∞¹[O₂Pb₃] Ribbons Based on OPb₄ Anion-Centered Tetrahedra in Pb₂(O₄Pb₈)(BO₃)₃Br₃ and Pb₂(O₈Pb₁₂)(BO₃)₂Br₆

The structures of two new lead-containing oxyborate bromines, Pb₂(O₄Pb₈)­(BO₃)₃Br₃ (<b>1</b>) and Pb₂(O₈Pb₁₂)­(BO₃)₂Br₆ (<b>2</b>), are determined by single-crystal X-ray diffraction for the first time. Both of them crystallize in the space group <i>C</i>2<i>/c</i> of the monoclinic crystal system. Although the two compounds have the same type of fundmental building units (FBUs), the OPb₄ anion-centered tetrahedra and BO₃ triangles, they exhibit different connection modes. Compound <b>1</b> consists of single _∞¹[OPb₂] chains, while compound <b>2</b> possesses _∞¹[O₂Pb₃] ribbons. Interestingly, large Br atoms profoundly influence the conformation of polyions based on the OPb₄ anion-centered tetrahedra, resulting in single _∞¹[OPb₂] chains linked up by finite zweier chains with four OPb₄ tetrahedra via the opposite edges in compound <b>1</b> and _∞¹[O₂Pb₃] ribbons with sequential condensation of OPb₂ chains in compound <b>2</b>. A detailed description of the effect of large Br atoms on the conformation of polyions is discussed. IR spectroscopy, UV–vis–NIR diffuse reflectance spectroscopy, and thermal analysis are also performed on the reported materials