Zintl phase as dopant source in the flux synthesis of Ba1−xKxFe2As2 type superconductors

Use of the Zintl phase KSn as a source of potassium dopant in tin flux syntheses of Ba(1-x)K(x)Fe(2)As(2) allows for incorporation of large amounts of potassium with much less attack on reaction vessels compared to the use of elemental potassium as a reactant; it also enables further study of tin incorporation into the products.