Borates have garnered a lot of attention in the realm of solid‐state chemistry due to their remarkable characteristics, in which the synthesis of borates with isolated [BO3] by adding rare‐earth elements is one of the main areas of structural design study. Five new mixed‐metal Y‐based rare‐earth borates, Ba2ZnY2(BO3)4, KNa2Y(BO3)2, Li2CsY4(BO3)5, LiRb2Y(BO3)2, and RbCaY(BO3)2, have been discovered using the high‐temperature solution approach. Isolated [BO3] clusters arranged in various configurations comprise their entire anionic framework, allowing for optical anisotropy tuning between 0.024 and 0.081 under 1064 nm. In this study, we characterize the relative placements of their [BO3] groups and examine how their structure affects their characteristics. The origin of their considerable optical anisotropy has been proven theoretically. This study unequivocally demonstrates that even a slight alteration to borates' anionic structure can result in a significant improvement in performance.

中文翻译：

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具有柔性[BO3]簇的稀土硼酸盐的可调谐光学各向异性

硼酸盐由于其显着的特性而在固态化学领域引起了广泛关注，其中通过添加稀土元素合成分离的[BO3]硼酸盐是结构设计研究的主要领域之一。利用高温高压发现了五种新的混合金属 Y 基稀土硼酸盐：Ba2ZnY2(BO3)4、KNa2Y(BO3)2、Li2CsY4(BO3)5、LiRb2Y(BO3)2 和 RbCaY(BO3)2。 ‐温度解决方案。以各种配置排列的孤立的 [BO3] 簇构成了它们的整个阴离子框架，允许在 1064 nm 下将光学各向异性调整到 0.024 到 0.081 之间。在这项研究中，我们描述了它们的 [BO3] 组的相对位置，并研究了它们的结构如何影响它们的特征。它们相当大的光学各向异性的起源已在理论上得到证明。这项研究明确表明，即使硼酸盐的阴离子结构发生轻微改变，也能显着提高性能。