Two new barium borate bromides: Ba2BO3Br and Ba3BO3Br3

• Ba2BO3Br and Ba3BO3Br3 have been grown by spontaneous crystallization.
• Ba2BO3Br is a stoichiometric compound with intergrowth structure as designed.
• Ba2BO3Br is composed by stacking of [Ba2(BO3)2]2− and [Ba2Br2]2+ slabs.
• Ba3BO3Br3 crystallizes in P−1 with zero dimensional [Ba12(BO3)4]12+ clusters.

Two new barium borate bromide crystals, Ba2BO3Br and Ba3BO3Br3, have been obtained by spontaneous crystallization. Ba2BO3Br crystallizes in P−3m1 space group, with cell parameters of a = 5.5157(10) Å, c = 11.019(4) Å, and Z = 2, its structure is build up by alternately stacking along c-axis of [Ba2(BO3)2]2− layers and bromide [Ba2Br2]2+ layers. The solved structure is analog to Ba2(BO3)1−x(CO3)xCl1+x except the interstitial halogen atoms at (0, 0, 1/2) is missing and accordingly the partly CO3 substitution for BO3 has not been observed. Ba3BO3Br3 crystallizes in a new structure type with P−1 space group and cell parameters of a = 9.280(4) Å, b = 9.349(7) Å, c = 13.025(9) Å, α = 92.71(3)°, β = 98.29(3)°, γ = 116.200(18)° and Z = 4. The basic structural unit in Ba3BO3Br3 is the clusters composed of 4 BO3 groups and 12 Ba atoms, which in turn are linked by eight Ba–O bonds with other four clusters to form sheets extend in the (001) plane.

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