2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/23773In this Communication we report about the unexpected effect of ruthenium doping in sodium ligthly-doped manganites. This effect seems to be in contrast with the usual model applied to describe the effect of this magnetic ion into the manganite structure. We propose a possible compensation mechanism which seems also able to describe other peculiar features encountered in these materials.3 pages, 2 Figures to appear in ChemCommMaterials Sciencetext