| Abstract
| - The layered double hydroxides (LDHs) Zn2Al(OH)6Cl·nH2O, Zn2Cr(OH)6Cl·nH2O, and Cu2Cr(OH)6Cl·nH2Ohave been shown to undergo staged intercalation reactions with succinate and tartrate anions. Monitoring theprocess in situ using energy-dispersive X-ray diffraction reveals the formation of second-stage intermediatescaused by the filling of every second layer. Depending on the nature of the organic anion, the Bragg peaksof the second-stage intermediates and the fully organic exchanged materials emerge in two distinct sequencesindicating two exchange pathways. For tartrate exchange, the fully exchanged material is not observed untilthe intermediate has gone through its maximum and the chloride precursor has disappeared completely, whilefor succinate exchange, the final state of intercalation and the second-stage intermediate simultaneously appear.Similar staging has previously been reported only for LiAl2(OH)6Cl·2H2O. These results demonstrate thatstaging in the intercalation of LDH does not involve a structural order of the host and cannot be explainedby a tactoid mechanism.
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