A comparative analysis of the three polymorphic structures H3, O10 and H12 of FeRhP

Abstract The phosphide FeRhP, belonging to a large series of ternary pnictides, exhibits very unusual metal ordering characteristics, depending on the applied synthesis route. It is demonstrated that size and electronegativity difference, that are the main criteria to consider for metal atom ordering, cancel out each other with the iron–rhodium couple.