On the Covalent Fields of Molecule-Surface Interactions

Edvin Fako; Philippe Schwaller

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arXiv · 2606.08619

On the Covalent Fields of Molecule-Surface Interactions

Edvin Fako·Philippe Schwaller

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Abstract

The ambiguity of the active site, the empirical status of Brønsted-Evans-Polanyi relations, and the unpredictability of linear scaling relation breakdown are three symptoms of a single representational choice: treating chemical affinity as an attribute of discrete geometric sites. Here we show that all three are resolved when chemical affinity is represented as a continuous property of the interface: the covalent field. We present a framework, Covalent Field Theory (CFT), in which active sites emerge as regions where the field sustains a bias toward bond formation beyond the thermal threshold, removing the need for geometric classification. Linear scaling relations are correlation structure in the field across probe families; their breakdown is a topological bifurcation with a precise geometric signature. Brønsted-Evans-Polanyi correlations arise from the covalent field decomposition, providing a theoretical basis for what has previously been treated as an empirical regularity, demonstrated across ~120,000 candidate pathways. Applied to a high-entropy alloy nanoparticle and a partially reduced high-entropy oxide, CFT maps these properties onto surfaces of arbitrary compositional and structural complexity.

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Edvin Fako, Philippe Schwaller. 2026-06-07. On the Covalent Fields of Molecule-Surface Interactions. https://arxiv.org/abs/2606.08619

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