Fluctuating Ru trimer precursor to a two-stage electronic transition in RuP

Superconductivity in binary ruthenium pnictides occurs proximal to and upon suppression of a mysterious non-magnetic ground state, preceded by pseudogap phase associated with Fermi surface instability, its critical temperature, T$_{c}$, is maximized around the quantum point. By analogy isoelectronic iron based counterparts, antiferromagnetic fluctuations became "usual suspects" as putative mediators superconducting pairing. Here we report on high temperature local symmetry breaking RuP, parent maximum-Tc branch these novel superconductors, revealed combined nanostructure-sensitive powder single crystal X-ray total scattering experiments. Large Ru$_{6}$ hexamer distortions orbital-charge trimerization form above two-stage electronic transition RuP. While ordering enables nonmagnetic state presumed complex oligomerization, relevance for superconductivity emerges distinct prospect. As metal system which partial d-manifold filling promotes instabilities, this represents further example precursors underpinning macroscopic collective behavior materials.