Definitive Crystal Structures Of Ortho-, Meta- And Para-Carboranes: Supramolecular Structures Directed Solely By C-H Center Dot Center Dot Center Dot O Hydrogen Bonding To Hmpa (Hmpa Equals Hexamethylphosphoramide)

Cocrystallisation of ortho- meta- and para-carboranes with hmpa (hexamethylphosphoramide) results in the isolation of 1:1 carborane,hmpa adducts which provide the first definitive X-ray structures of the unsubstituted carboranes as part of three very different C-H...O hydrogen-bonded supramolecular structures.