One way to induce insulator-to-metal transitions in the spin-orbit Mott insulator Sr 2 IrO 4 is to substitute iridium with transition metals (Ru, Rh). However, this creates intriguing inhomogeneous metallic states, which cannot be described by a simple doping effect. We detail the electronic structure of the Ru-doped case with angle-resolved photoemission and show that, in contrast to Rh, it cannot be connected to the undoped case by a rigid shift. We further identify bands below E F coexisting with the metallic ones that we assign to nonbonding Ir sites. We rationalize the differences between Rh and Ru by a different hybridization with oxygen, which mediates the coupling to Ir and sensitively affects the effective doping. We argue that the spin-orbit coupling does not control either the charge transfer or the transition threshold.

Unfolding of a supercell band structure into a primitive Brillouin zone is important for understanding implications of structural distortions, disorder, defects, solid solutions on materials electronic structure. Necessity of the band unfolding is also recognised in interpretation of angleresolved photoemission spectroscopy (ARPES) measurements. We describe an extension of the fold2Bloch package by implementing an arbitrary transformation matrix used to establish a relation between primitive cell and supercell. This development allows us to overcome limitations of supercells constructed exclusively by scaling of primitive cell lattice vectors. It becomes possible to transform between primitive and conventional cells as well as include rotations. The fold2Bloch is publicaly available from a GitHub repository as a FORTRAN code. It interfaces with the allelectron full-potential WIEN2k and the pseudopotential VASP density functional theory packages.The fold2Bloch is supplemented by additional pre-and post-processing utilities that aid in generating k points in the supercell (such that they later fall onto a desired path in the primitive Brillouin zone after unfolding) and plotting the unfolded band structure. We selected Sr 2 IrO 4 as an illustrative example and, for the first time, present its properly unfolded band structure in direct comparison with ARPES measurements. In addition, critical importance of the band unfolding for interpretation of SrIrO 3 ARPES data is illustrated and discussed as a perspective. I. INTRODUCTIONThe band dispersion E(k) obtained from electronic structure calculations provides information about Fermi surface of metals, direct/indirect transition in semiconductors, effective masses, etc. When periodicity is perturbed (e.g., solid solutions, defects, magnetic order) the Brillouin zone (BZ) shrinks and bands get folded. As a result, E(k) becomes obscured and difficult to interpret.Even when the periodicity is formally perturbed, it is still possible to recover an effective band structure in a BZ of the primitive cell using a k-spectral decomposition also known as 'band unfolding'. There are numerous examples of band unfolding. The notable milestones include an electronic structure of aperiodic solids [1-3], solid solutions described within a

Sr2IrO4 and Sr3Ir2O7 form two families of spin-orbit Mott insulators with quite different charge gaps and an antiferromagnetic (AF) ground state. This offers a unique opportunity to study the impact of long-range magnetic order in Mott insulators. It appears to play a different role in the two families, as there is almost no change of the resistivity at the magnetic transition TN in Sr2IrO4 and a large one in Sr3Ir2O7. We use angle-resolved photoemission to study the evolution of the spectral lineshape through the magnetic transition. We use Ru and La substitutions to tune TN and discriminate changes due to temperature from those due to magnetic order. We evidence a shift and a transfer of spectral weight in the gap at TN in Sr3Ir2O7, which is absent in Sr2IrO4. We assign this behavior to a significantly larger coherent contribution to the spectral lineshape in Sr3Ir2O7, which evolves strongly at TN . On the contrary, the Sr2IrO4 lineshape is dominated by the incoherent part, which is insensitive to TN . We compare these findings to theoretical expections of the Slater vs Mott antiferromagnetism within Dynamical Mean Field Theory.