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arXiv · 2601.04460

A Structural Map of Potential Correlated Electron Molecular Orbital Materials

Md. Rajbanul Akhond·Alexandru B. Georgescu
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Abstract

Correlated electron molecular orbital (CEMO) materials host emergent electronic states built from molecular orbitals localized over clusters of transition metal ions in a solid, yet have historically been discovered sporadically and generally been treated as isolated case studies. Here, we present criteria and tools to classify and analyze these materials, provide a database of identified materials with cluster-specific symmetry analysis, including cluster point groups, effective cluster sublattice dimensionality. Our electronic structure analysis shows that narrow bands in cluster materials can arise either from relatively isolated cluster molecular orbitals or from a mixed mechanism in which cluster localization coexists with frustrated-lattice flat-band topology. We discuss how CEMO properties do not arise from metal clusters in a solid alone: rather they depend on electron count, symmetry, frustration and correlation strength. By integrating cluster classification with flat-band lattice topology and electrochemistry-relevant information, we provide further relevant information to multiple scientific communities. Applying this approach in a high-throughput screen of 34,548 compounds yields potential 2,627 stable or metastable CEMO compounds with isolated cluster motifs. The accompanying open dataset, Cluster Finder software, and interactive web platform enable systematic exploration of cluster-containing electronic solid state materials and establish a starting point for discovering a new class of correlated quantum materials with a wide array of properties.

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Md. Rajbanul Akhond, Alexandru B. Georgescu. 2026-09-09. A Structural Map of Potential Correlated Electron Molecular Orbital Materials. https://arxiv.org/abs/2601.04460

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