High-temperature behaviour of lithium borates: Part II: High-temperature X-ray diffractometric and dilatometric studies

High-temperature X-Ray diffractometric (HTXRD) and dilatometric studies of lithium borates, namely Li 3BO 3, α-Li 4B 2O 5, β-Li 4B 2O 5, Li 6B 4O 9, α-LiBO 2, Li 2B 4O 7, Li 3B 7O 12 LiB 3O 5, and Li 2B 8O 13 have been carried out, which revealed that Li 2B 8O 13 underwent a solid-phase transition from triclinic to monoclinic at temperatures >543 K in air. The variation in lattice parameters with temperature, unit-cell volume as well as linear coefficient of thermal expansion ( α a , α b and α c ), volume expansion of the unit cell ( α v) of the compounds as well as bulk thermal expansion coefficients have been determined by HTXRD and dilatometry respectively.