Synthesis and Crystal Structure of the High-pressure Iron Borate β-FeB2O4
Synthesis and Crystal Structure of the High-pressure Iron Borate β-FeB2O4
复制标题
高压硼酸铁β-FeB2O4的合成及晶体结构
DOI：
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发表时间：
2008
期刊：
影响因子：
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通讯作者：
H. Huppertz
中科院分区：
文献类型：
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作者：
S. Neumair;R. Glaum;H. Huppertz
在8 GPa和1030 ℃的高温高压条件下合成了硼酸铁β -FeB 2 O 4。β -FeB 2 O 4的结构与HP-NiB 2 O 4是同型的，代表了硼酸盐的第二个例子，其中每个BO 4四面体与第二个四面体共享一个公共边。β -FeB_2O_4晶体属C_2/c（Z = 4）空间群，晶胞参数a = 950.0（2），B = 562.9（2），c = 443.7（1）pm，β = 108.50（3）nm，V = 0.22495（8）nm ~ 3，R1 = 0.0293，wR 2 = 0.0647（所有数据）。该结构由BO 4四面体层组成，通过共享边缘的FeO 6八面体串连接。从β -FeB 2 O 4的极化单晶电子吸收光谱估计出配位场分裂Δo = 8860 cm−1。[FeIIO 6]发色团中配位场的四重畸变为−（8/3）dσ <$2900 cm−1。在16000 cm−1 ≤ 1000 cm− 1 ≤24000 cm−1范围内，观察到[FeIIO 6]发色团内较强的自旋禁戒跃迁。
The iron borate β -FeB2O4 was synthesized under high-pressure / high-temperature conditions of 8 GPa and 1030 ◦C. The structure of β -FeB2O4 is isotypic to HP-NiB2O4, representing the second example of a borate in which every BO4 tetrahedron shares a common edge with a second one. β - FeB2O4 crystallizes in the space group C2/c (Z = 4) with the parameters a = 950.0(2), b = 562.9(2), c = 443.7(1) pm, β = 108.50(3)◦, V = 0.22495(8) nm3, R1 = 0.0293, and wR2 = 0.0647 (all data). The structure consists of layers of BO4 tetrahedra, connected via strings of edge-sharing FeO6 octahedra. A ligand field splitting of Δo ≈8860 cm−1 is estimated from polarized single-crystal electronic absorption spectra of β -FeB2O4. The tetragonal distortion of the ligand field in the [FeIIO6] chromophore amounts to −(8/3)dσ ≈2900 cm−1. In the range of 16000 cm−1 ≤ṽ ≤24000 cm−1, rather strong spin-forbidden transitions within the [FeIIO6] chromophore are observed Graphical Abstract Synthesis and Crystal Structure of the High-pressure Iron Borate β-FeB2O4