Zn- and Co-based layered double hydroxides: prediction of the a parameter from the fraction of trivalent cations and vice versa.

A recently proposed method to calculate the a parameter of the unit cell of layered double hydroxides from the fraction of trivalent cations is extended to Zn- and Co-based phases. It is shown to be useful as a sanity test for extant and future structure determinations and computer-simulation studies.