We generated outputs by calling our models only once, without sampling for the best generation, and found that fine-tuned models successfully suggest code or CIF files that convert into valid structures in most cases (see Figure ). Our fine-tuned LLMs produced hallucinationswhere the parser fails to generate a valid structurein only 5% to 14% of cases. These hallucinations often stem from the error: 'supplied space group is incompatible with the supplied lattice parameters.'