polyborate
Polyborates are a class of inorganic polymers consisting of boron-oxygen units linked by shared oxygen atoms to form extended networks. They can be solid crystalline materials or solvated species in aqueous solution. In polyborates, boron is present predominantly in three-coordinate [BO3] triangles and four-coordinate [BO4] tetrahedra; these units connect through B–O–B bridges, producing one-dimensional chains, two-dimensional sheets, or three-dimensional frameworks. The specific connectivity depends on synthesis conditions such as temperature, concentration, pH, and the presence of counterions or ligands.
In solution, polyborate species arise by condensation of boric acid and borate units under alkaline conditions
Polyborates are related to simpler borate species, including metaborates, diborates, and orthoborates, but collectively denote higher-order