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Antiferromagnetic intermetallic compound EuRhGe3 crystalizes in a non-centrosymmetric BaNiSn3-type (I4mm) structure. We studied its pressure-dependent crystal structure by using synchrotron powder x-ray diffraction at room temperature. Our results show a smooth contraction of the unit cell volume by applying pressure while preserving I4mm symmetry. No structural transition was observed up to 35 GPa. By the equation of state fitting analysis, the bulk modulus and its pressure derivative were determined to be 73 (1) GPa and 5.5 (2), respectively. Furthermore, similar to the isostructural EuCoGe3, an anisotropic compression of a and c lattice parameters was observed. Our experimental results show a good agreement with the pressure-dependent structural evolution expected from theoretical calculations below 13 GPa. Reflecting a strong deviation from integer Eu valence, the experimental volume data appear to be smaller than those of DFT calculated values at higher pressures.

Murunskite (K$_2$FeCu$_3$S$_4$) is a bridging compound between the only two known families of high-temperature superconductors. It is a semiconductor like the parent compounds of cuprates, yet isostructural to metallic iron-pnictides. Moreover, like both families, it has an antiferromagnetic (AF)-like response with an ordered phase occurring below $\approx$ 100 K. Through comprehensive neutron, M\"ossbauer, and XPS measurements on single crystals, we unveil AF with a nearly commensurate quarter-zone wave vector. Intriguingly, the only identifiable magnetic atoms, iron, are randomly distributed over one-quarter of available crystallographic sites in 2D planes, while the remaining sites are occupied by closed-shell copper. Notably, any interpretation in terms of a spin-density wave is challenging, in contrast to the metallic iron-pnictides where Fermi-surface nesting can occur. Our findings align with a disordered-alloy picture featuring magnetic interactions up to second neighbors. Moreover, in the paramagnetic state, iron ions are either in Fe$^{3+}$ or Fe$^{2+}$ oxidation states, associated with two distinct paramagnetic sites identified by M\"ossbauer spectroscopy. Upon decreasing the temperature below the appearance of magnetic interactions, these two signals merge completely into a third, implying an orbital transition. It completes the cascade of (local) transitions that transform iron atoms from fully orbitally and magnetically disordered to homogeneously ordered in inverse space, but still randomly distributed in real space., Comment: 17 pages, 8 figure, 2 tables (9 pages, 4 figures in the main text; 8 pages, 4 figures, 2 tables in the appendix)

We study the structure of single $\Lambda$-hypernuclei using the Hartree--Fock--Bogoliubov method. Finite range Gogny-type forces are used to describe the nucleon-nucleon and $\Lambda$-nucleon interactions. Three different $\Lambda$-nucleon Gogny forces are built. The unknown parameters of these forces are obtained by fitting the experimental binding energies of the $1s$ $\Lambda$ single-particle state in various hypernuclei using the ``Simulated Annealing Method''. These forces are then used to calculate the binding energies of the other ($1p, 1d, 1f, 1g$) $\Lambda$ single-particle states in the different hypernuclei. The predicted values are found to be in good agreement with the experimental data for the three forces constructed. In addition, we calculate also the root-mean-square radii of ground state $\Lambda$ orbital, as well as several global properties of the hypernuclei considered such as their ground-state Hartree--Fock--Bogoliubov energy, their pairing energy and their quadrupole moment., Comment: 8 pages, 2 figues, 3 tables