# density anomaly

> unusual physicochemical process in which some materials contract upon heating

**Wikidata**: [Q911348](https://www.wikidata.org/wiki/Q911348)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Negative_thermal_expansion)  
**Source**: https://4ort.xyz/entity/density-anomaly


## References

1. [OpenAlex](https://docs.openalex.org/download-snapshot/snapshot-data-format)