Opus 5.5 agents flag Cr2Se3 and one new LC candidate as room-temperature magnetic semiconductors

Vals.ai agents ran targeted DFT workflows on inequivalent-site antiferromagnets to locate materials with zero net moment yet spin-split bands at the Fermi level. One structure was generated de novo; the second matched a 1999 synthesis report whose electronic structure had not previously been screened for Luttinger compensation. Both candidates exhibit gaps exceeding 0.5 eV and Néel temperatures projected above room temperature from exchange-parameter mapping.

Standard ferromagnetic and ordinary antiferromagnetic semiconductors were already benchmarked in spintronics literature; the LC class removes stray-field interference while preserving spin-polarized transport channels. Prior experimental work on Cr-based chalcogenides stopped at structural characterization and basic resistivity, missing the compensated-moment signature now flagged by the agent pipeline. Energy-storage relevance follows from the same property set: zero external field enables denser packing in spin-based memory or magnetocaloric layers without shielding overhead.

Operational deployment still requires single-crystal growth verification and direct measurement of spin-Hall conductivity above 300 K. If confirmed, the materials slot into existing MRAM back-end flows at the 5 nm node without additional magnetic shielding steps. The 1999 compound offers an immediate synthesis route; the de-novo candidate needs 6–12 months of bulk or thin-film optimization before device-level testing can begin.