arXiv Machine Learning By Lecheng Kong, Xiyuan Wang, Yixin Chen, Muhan Zhang

Round-trip Reinforcement Learning: Self-Consistent Training for Better Chemical LLMs

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The paper introduces Round-Trip Reinforcement Learning (RTRL), a framework that trains chemical language models to improve round‑trip consistency by rewarding successful forward and reverse transformations. By iteratively training forward and reverse mappings, RTRL leverages abundant unlabeled chemical data to enhance both consistency and overall performance across supervised, self‑supervised, and synthetic data regimes. Experiments show that RTRL outperforms strong baselines, demonstrating that round‑trip consistency can be treated as a trainable objective for more robust foundation models.

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