Structural, electronic, and magnetic properties of pyrochlore Nd₂Ir₂O₇ studied by first-principles calculations

First-principle calculations have been performed on the Nd-based pyrochlore iridate, Nd ₂ Ir ₂ O ₇ , to investigate electronic structures and magnetic properties. The generalized gradient approximation formalism, GGA, has been used to correct the string onsite Coulomb repulsion energy (U) between localized 5d and 4f electrons. Our present study found that combinations of U value on Nd, Uf , and Ir, Ud affect the electronic and magnetic properties of Nd ₂ Ir ₂ O ₇ . Setting Uf and Ud to be 5 eV for each, the all-in-all-out (AIAO) magnetic spin structure gives rise to a small Ir ⁴⁺ magnetic moment of 0.37 μ B and Nd ³⁺ magnetic moment of 3.00 μ B , a band gap of Nd ₂ Ir ₂ O ₇ was estimated to be 1.50 eV starting to open a sizable band gap to change the system from metal to insulator and stable in ferromagnetic phase.