Structural intergrowth in the CaxLa1?xFeO3?x2 system (0 ≤ x ≤ 1): An electron microscopy study

An electron microscopy and diffraction study of several samples of the system $\text{Ca}{}_{\mathrm{x}}\text{La}{}_{\mathrm{1?x}}\text{FeO}{}_{\mathrm{<mtext>3?</mtext><mtext>x</mtext><mtext>2</mtext>}}$ shows these solids to be formed by the disordered intergrowth of two out of three of the ordered terms corresponding to $\text{x = 0, x =}\text{2}\text{3}$, and x = 1 (i.e., LaFeO₃, Ca₂LaFe₃O₈, and Ca₂Fe₂O₅). The relative amounts of the intergrowing individuals vary with x and may extend down to unit cell thickness; i.e., to the level of isolated extended defects.