The ammonium borate NH₄B₁₁O₁₆(OH)₂ has been successfully synthesized by a mild hydrothermal method. Its structure features a new fundamental building block (FBB) [B₁₁O₁₈(OH)₂], which is composed of a [B₅O₁₀] double-ring and two [B₃O₅(OH)] single-rings via sharing corner oxygen atoms. The FBB further condenses into 2D wavy-shaped polycyclic layers ²_∞[B₁₁O₁₆(OH)₂] and forms the final framework through hydrogen bonding. Specifically, the effect of the hydroxyl to boron ratio (N_OH/N_B) on the FBB assembly has been investigated in the ammonium borate system. In addition, the optical and thermal properties of this compound have been studied experimentally. First-principles calculations have also been carried out in order to understand the electronic structure.

中文翻译：

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NH ₄乙₁₁ ø ₁₆（OH）₂：新的硼酸盐波浪形多环铵² _∞ [B ₁₁ ø ₁₆（OH）₂ ]的层

硼酸铵NH ₄ B ₁₁ O ₁₆（OH）₂已通过温和的水热法成功合成。它的结构具有一个新的基本构件（FBB）[B ₁₁ O ₁₈（OH）₂ ]，它由一个[B ₅ O ₁₀ ]双环和两个[B ₃ O ₅（OH）]单环组成。通过分享角落的氧原子。在FBB进一步凝结成2D波浪形多环层² _∞ [B ₁₁ ø ₁₆（OH）₂]并通过氢键形成最终的骨架。具体而言，已在硼酸铵系统中研究了羟基与硼之比（N _OH / N _B）对FBB组件的影响。另外，已经对该化合物的光学和热学性质进行了实验研究。为了理解电子结构，还进行了第一性原理计算。