Crystal structure of KBe2BO3F2
Crystal structure of KBe2BO3F2
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DOI:
10.1524/zkri.1995.210.2.93
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发表时间:
1995-02
影响因子:
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通讯作者:
L.-m. Mei;X. Huang;Y. Wang;Q. S. Wu;B. Wu;C. Chen
中科院分区:
文献类型:
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作者:
L.-m. Mei;X. Huang;Y. Wang;Q. S. Wu;B. Wu;C. Chen
Potassium beryllium borate fluoride, KBe 2 BO 3 F 2 , is rhombohedral (hexagonal axes) R32 (No. 155), a = b = 4.427(4) A, c = 18.744(9) A, V = 318.3(4) A 3 , M = 153.93, D m = 2.40 g . cm −3 , D x = 2.41 g . cm −3 for Z = 3, F (000) = 222, μ = 11.84 cm −1 , T = 296 K. The crystal structure has been determined by single crystal X-ray diffraction and final R value for 260 unique reflections with I > 3(I) is 3.1%. The results reveal a new type of complex polyanions. All B atoms are planar triangularly coordinated while all Be atoms are tetrahedrally coordinated. The feature of the borate framework is infinite sheets [Be 2 BO 3 F 2 ] which may be described in terms of six-membered rings of [Be 2 BO 6 F 2 ] having Be-O and B-O edges in common. The nonlinear optical (NLO) properties of this compound are also discussed here and the [BO 3 ] 3− anionic groups are principally responsible for the second harmonic generation (SHG) effect