Pb2.28Ba1.72B10O19 featuring a three-dimensional B–O anionic network with edge-sharing [BO4] obtained under ambient pressure

The first borate featuring a three-dimensional B–O anionic network with edge-sharing (ES) [BO4] units, Pb2.28Ba1.72B10O19 (PbBaBO), has been synthesized under ambient pressure. The squeezing effect of the 2∞[B10O19] bilayer structure on the intra-layer co-edge [BO4] leads to an extremely long B–B distance and quite small internal O–B–O angles in the [B2O6] ring.