Inducing Complexity in Intermetallics through Electron–Hole Matching: The Structure of Fe 14 Pd 17 Al 69

We illustrate how the crystal structure of Fe 14 Pd 17 Al 69 provides an example of an electron–hole matching approach to inducing frustration in intermetallic systems. Its structure contains a framework based on IrAl 2.75 , a binary compound that closely adheres to the 18− n rule. Upon substituting the Ir with a mixture of Fe and Pd, a competition arises between maintaining the overall ideal electron concentration and accommodating the different structural preferences of the two elements. A 2×2×2 supercell results, with Pd‐ and Fe‐rich regions emerging. Just as in the original IrAl 2.75 phase, the electronic structure of Fe 14 Pd 17 Al 69 exhibits a pseudogap at the Fermi energy arising from an 18− n bonding scheme. The electron–hole matching approach's ability to combine structural complexity with electronic pseudogaps offers an avenue to new phonon glass–electron crystal materials.