NaK15[B4O5(OH)4]6(NO2)2(CO3)·7H2O: Assembly of an unprecedented mixed anion inorganic compound via a facile hydrothermal route

The combination of multiple anions into one compound leads to new structure types with intriguing properties. Here, a new mixed anion compound NaK15[B4O5(OH)4]6(NO2)2(CO3)·7H2O has been synthesized by the hydrothermal method. Notably, this compound simultaneously possesses [B4O5(OH)4]2−, [NO2]−, and [CO3]2− fundamental building blocks, which is the first case combining the feature of borates, nitrites, and carbonates.