Making Claude a chemist

This post details Anthropic's initial work in applying Claude models to chemistry, specifically evaluating their performance on interpreting NMR spectra and elucidating molecular structures. It presents a quantitative assessment comparing Claude Opus 4.7, Opus 4.6, and Sonnet 4.6 against dedicated chemistry software (ChemDraw and MestReNova) on forward prediction of NMR spectra and inverse prediction (structure elucidation). The evaluation methodology, including the dataset of 20 compounds and the metrics used (ppm error, peak splitting pattern matching), is described. The post highlights Claude's competitive performance, particularly Opus 4.7's accuracy in predicting peak positions and splitting patterns, and its ability to perform inverse elucidation from spectra and molecular formulas. Limitations of the current evaluation, such as dataset size and scope of chemical scaffolds, are also discussed, along with future directions for improving Claude's chemical reasoning capabilities.