Electronic structure along Sm2Co3Ge5 twin boundaries

Ln2Co3Ge5 (Ln = lanthanide) intermetallics possess intriguing electronic and magnetic properties. The compound Sm2Co3Ge5 exhibits antiferromagnetic ordering coupled with a magnetic moment that exceeds the theoretical moment of trivalent Sm suggesting a magnetic contribution from Co. Twinning is observed in Sn flux -grown monoclinic Sm2Co3Ge5 along (100) planes. While the influence of twin boundaries on superconducting oxides and 2D -materials is well -studied, its effects on bulk lanthanide -based intermetallics are rarely explored. Using monochromated electron energy -loss spectroscopy (EELS) and high -resolution transmission electron microscopy (TEM), we investigate the impact of twin domains on the local strain and electronic structure of Sm2Co3Ge5. The boundaries between twinned domains primarily exhibit shear strain and have a constant oxidation state, but fine structure emerges in the Co L2,3 edges at twin boundaries, indicative of 3d -electron hybridization and occupation of states not present in bulk grain spectra. These findings provide insights into tuning the bulk properties of lanthanide -transition metal systems with complex magnetism.