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Perovskite-type oxide has a general formula ABO_3. Both the lattice A- and lattice B-sites can be occupied by two kinds of metallic ions, forming substituted perovskites such as La_(1-x)Sr_xCoO_3-d and LaFe_xCo_(1-x)O_3. In the present work, we aim to investigate competitive occupying of Fe~(3+) and Co~(3+) ions into the lattice B-sites of perovskite LaFe_xCo_(1-x)O_3 formed under the condition of excess feeding of Fe~(3+) and Co~(2+) ions relative to the La~(3+) ions. For this purpose, standard curve of normalized cell volumes(NCVs) of a defined series of perovskites LaFe_xCo_(1-x)O_3 versus the x values was plotted. Lattice occupancy of Fe~(3+) ions at the B-sites of the perovskite LaFe_xCo_(1-x)O_3 was then determined from the standard curve. It is proved that Fe~(3+) ions were capable of occupying preferentially into the lattice B-sites of the perovskite crystalline structure.
Both the lattice A-and lattice B-sites can be occupied by two kinds of metallic ions, forming substituted perovskites such as La_ (1-x) Sr_xCoO_3-d and LaFe_xCo_ (1-x ) O_3. In the present work, we aim to investigate competitive occupying of Fe ~ (3+) and Co ~ (3+) ions into the lattice B-sites of perovskite LaFe_xCo_ (1-x) O_3 formed under the condition of excess feeding of Fe ~ (3+) and Co ~ (2+) ions relative to the La ~ (3+) ions. For this purpose, the standard curve of normalized cell volumes (NCVs) of a defined series of perovskites LaFe_xCo_ (1- x) O_3 versus the x values was plotted. Lattice occupancy of Fe ~ (3 +) ions at the B-sites of the perovskite LaFe_xCo_ (1-x) O_3 was then determined from the standard curve 3+) ions were capable of occupying preferentially into the lattice B-sites of the perovskite crystalline structure.