[C₆N₄H₂₄]CoBe₆P₆O₂₄·3H₂O: A novel 3-dimensional beryllophosphate zeolite-like structure encapsulating Co^II ions

A novel cobalt beryllophosphate (CBP-CHA) with the chabazite framework topology has been hydrothermally synthesized by using a metal amine complex as a starting material. The structure was solved by single-crystal X-ray diffraction {crystal data for [C₆N₄H₂₄]CoBe₆P₆O ₂₄·3H₂O: M = 889.14, rhombohedral, space group R3̄, a = 12.380(3), b = 12.380(3), c = 14.558(5) Å, V = 1932.5(10) ų, Z = 3, R₁ = 0.0878, R_w = 0.1929}. The compound is unusual in that it is not only the first organically-templated CoBePO₄ phase, but it is also the first instance where Co^II ions are trapped in the double 6-ring (D6R) of the structure of CBP-CHA. A cobalt atom locates at the 3-fold axis in each D6R, chemically bonding to framework oxygen atoms and leading to contraction of the D6R. CBP-CHA has 3-dimensional 8-ring channels along the crystallographic [100] and [010] directions. The framework charges of CBP-CHA are balanced by both the protonated amines in the channel and Co^II ions trapped in the D6R.