Add pointer to artifacts branch

README.md

@@ -46,11 +46,14 @@ to manage the datasets. This allows us to
 
 ## Structure of the repo
 
-- [`datasets/`](./datasets/) each subfolder contains a dataset for a specific system
+The tarballs are stored in the [`artifacts` branch](https://huggingface.co/datasets/atomology/WannierDatasets/tree/artifacts).
+
+While in the [`main` branch](https://huggingface.co/datasets/atomology/WannierDatasets/tree/main), the structure of the repo is as follows:
+- [`datasets/`](./datasets/) each subfolder contains a dataset as well as input/output files for one material
 - [`pseudo/`](./pseudo/) pseudopotentials used when generating the datasets
 - [`src/`](./src/) a fake folder just to make `Project.toml` happy
 
 ## Contributing
 
 If you feel your dataset is useful for the community, please feel free to contribute.
-Please have a look at the [contributing guidelines](./docs/CONTRIBUTING.md).
+Please have a look at the [contributing guidelines](./docs/CONTRIBUTING.md).