Li8[B16O26(OH)4] · 6H2O: A novel lithium borate with a larger polyborate anion

A novel hydrated lithium borate, Li8[B16O26(OH)4] · 6H2O, has been hydrothermally synthesized and characterized by single crystal X-ray diffraction, FT-IR spectroscopy, and simultaneous TGA–DTA. Its crystal structure consists of Li–O polyhedra and polyborate anionic layers constructed by the unprecedented [B16O26(OH)4]8− unit. The layered networks are stacked by ABAB fashion and each sheet contains the largest odd 13-membered boron rings.