Update README.md

Updating README with dataset features, subdirectories, citation, and contact. Fix links to preprint and github later.

README.md

@@ -1,3 +1,57 @@
----
-license: apache-2.0
----
+---
+license: apache-2.0
+tags:
+- chemistry
+size_categories:
+- 10K<n<100K
+---
+
+# TrajCast Dataset arXiv 2025
+
+This dataset contains atomic configurations of molecular and condensed matter systems used to train, validate, and test the *TrajCast* framework for forecasting molecular dynamics (MD) trajectories using autoregressive equivariant message-passing networks.
+Each entry represents a snapshot from a MD trajectory, defined by the chemical elements, instantaneous positions, and velocities of all atoms, along with information about their state at a slightly later time interval Δt. 
+
+## Subdirectories
+
+The dataset includes data for the models presented and benchmarked in our [preprint](https://arxiv.org/), with time intervals varying for each system. 
+Additionally, we provide a small example dataset to help you get started with our [example notebooks](https://github.com/IBM).
+
+- **paracetamol**: Dataset for gas-phase paracetamol (20 atoms) using a time interval of 7 fs.
+- **quartz**: Data for crystalline quartz (162 atoms) using a time interval of 30 fs.
+- **water**: Data for liquid bulk water (192 atoms) using a time interval of 5 fs.
+- **example**: Subset of dataset for gas-phase paracetamol (20 atoms) using a time interval of 7 fs. About 5-10 % of the full dataset.
+
+## Dataset Features
+
+The data comes in `.extxyz` format and we follow the units of style `real` from [LAMMPS](https://docs.lammps.org/units.html). Each entry correspondgs to an atomic configuration and includes the following fields:
+
+- **species**: The type of atom (e.g., C for Carbon, O for Oxygen (O), ...).
+- **positions**: 3D atomic positions (in Angstroms).
+- **velocities**: 3D atomic velocities (in Angstroms per fs).
+- **displacements**: 3D atomic displacements to the new positions after time interval Δt (in Angstroms).
+- **update_velocities**: 3D atomic velocities at time interval Δt (in Angstroms per fs).
+- **timestep**: Time interval Δt (in femtoseconds).
+- **pbc**: Information about periodic boundary conditions (e.g., `T T T`).
+- **Lattice**: The lattice vectors of the simulation box.
+- **num_atoms**: The total number of atoms in the system (first line).
+
+
+## Citation
+
+If you decide to use this dataset, please consider citing our preprint
+
+```
+@misc{Thiemann2025Force-Free,
+      title={Force-Free Molecular Dynamics Through Autoregressive Equivariant Networks}, 
+      author={Thiemann, Fabian L and Reschützegger, Thiago, and Olarte-Plata, Juan D. and Taddese, Tseden and Esposito, Massimiliano, and Martelli, Fausto},
+      year={2025},
+      eprint={...},
+      archivePrefix={arXiv},
+      primaryClass={...},
+      url={https://arxiv.org/...}, 
+}
+```
+
+## Contact
+
+For more information or if you like to contribute, please reach out to [email protected].