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Synthesis and crystal structure of a new strontium borate, Sr2B16O26

2007; Elsevier BV; Volume: 10; Issue: 7 Linguagem: Inglês

10.1016/j.solidstatesciences.2007.10.029

1873-3085

Zhi‐Hua Tang, Xuean Chen, Ming Li,

X-ray Diffraction in Crystallography

Abstract A new strontium borate, Sr 2 B 16 O 26 , has been prepared by solid-state reactions at temperature below 750 °C. The single-crystal X-ray structural analysis showed that Sr 2 B 16 O 26 crystallizes in the monoclinic space group P 2 1 / c with a = 8.408(1) A, b = 16.672(2) A, c = 13.901(2) A, β = 106.33(1)°, and Z = 4. Its crystal structure consists of a 3D network of the complex borate anion [B 16 O 20 O 12/2 ] 4− , formed by 12 BO 3 triangles and 4 BO 4 tetrahedra, which can be viewed as 3 linked [B 3 O 3 O 4/2 ] − triborate groups bonded to 1 pentaborate [B 5 O 6 O 4/2 ] − group and 2 BO 3 triangles; this leads to a Fundamental Building Block (FBB) with the shorthand notation 16: ∞ 3 [3 × (3:2Δ + T) + (5:4Δ + T) + 2Δ]. The 3D network affords intersecting open channels running parallel to the crystallographic a and c axes, where Sr 2+ cations reside. The IR spectrum further confirms the presence of both BO 3 and BO 4 groups.