Researchers tested how well language models learn from data that combine coordinates with categories, a format used to describe crystal structures and predict properties such as formation energy and elastic modulus. Using synthetic datasets and the MatText benchmarking framework, they varied how much the coordinates and categories contributed to the answer.

The language models performed well on category-based patterns but consistently failed to capture the coordinate information. This limitation remained in tests of models with up to 70 billion parameters, datasets containing up to 2 million structures and different text representations. Models designed specifically to use geometric information outperformed the language models on material-property tasks dominated by structure.