A fundamental advance in the intercalation chemistry of clays is the f
ormation for the first time of smectite clay heterostructures with reg
ularly stratified organic and inorganic exchange cations, e.g. the flu
orohectorite heterostructure with gallery cations Na+ and C16H33PBU3shown in the figure. Their transformation into rectorite-like alumina
pillared analogues is also demonstrated.