$A-B$ interatomic minimum distances and $A$-O maximum distances (indicating the limit of the second coordination-sphere) for (a) lanthanum [115, 116], (b) praseodymium, and (c) neodymium compounds [120], as a function of the $B$-site cation radii ( $\AA$); showing which materials have $B$-site cations inside the second coordination-sphere. Mg compounds are shown in red, to indicate the particular behavior attributed to cation type.
A-B interatomic minimum distances and A-O maximum distances (indicating the limit of the second coordination-sphere) for (a) lanthanum [115, 116], (b) praseodymium, and (c) neodymium compounds [120], as a function of the B-site cation radii ( \AA); showing which materials have B-site cations inside the second coordination-sphere. Mg compounds are shown in red, to indicate the particular behavior attributed to cation type.