Formation of Second-Stage Intermediates in Anion-Exchange Intercalation Reactions of the Layered Double Hydroxide [LiAl₂(OH)₆]Cl·H₂O As Observed by Time-Resolved, in Situ X-ray Diffraction

Time-resolved in situ energy-dispersive X-ray diffraction studies on the intercalation of dicarboxylate anions (Na 2 C 4 H 4 O 4, Na 2 C 6 H 8 O 4, Na 2 - trans -C 4 H 2 O 4, Na 2 - cis -C 4 H 2 O 4, Na 2 - l -C 4 H 4 O 5, Na 2 -1,2-C 8 H 4 O 4, Na 2 -1,4-C 8 H 4 O 4 ) into [LiAl 2 (OH) 6 ]Cl·H 2 O have revealed the rapid formation of a second-stage intermediate phase that subsequently transforms into a phase-pure fully ion-exchanged product. These intermediates can be isolated as pure crystalline phases by reaction of the host lattice with stoichoimetric amounts of the dicarboxylate anions.