diff --git a/torchmdnet/datasets/ace.py b/torchmdnet/datasets/ace.py
index e2470dcb2..75869a771 100644
--- a/torchmdnet/datasets/ace.py
+++ b/torchmdnet/datasets/ace.py
@@ -8,6 +8,81 @@
 
 
 class Ace(Dataset):
+    """The ACE dataset.
+
+    This dataset is sourced from HDF5 files.
+
+    Mandatory HDF5 file attributes:
+    - `layout`: Must be set to `Ace`.
+    - `layout_version`: Can be `1.0` or `2.0`.
+    - `name`: Name of the dataset.
+
+    For `layout_version` 1.0:
+    - Files can contain multiple molecule groups directly under the root.
+    - Each molecule group contains:
+      - `atomic_numbers`: Atomic numbers of the atoms.
+      - `formal_charges`: Formal charges of the atoms. The sum is the molecule's total charge. Units: electron charges.
+      - `conformations` subgroup: This subgroup has individual conformation groups, each with datasets for different properties of the conformation.
+
+    For `layout_version` 2.0:
+    - Files contain a single root group (e.g., a 'master molecule group').
+    - Within this root group, there can be multiple molecule groups.
+    - Each molecule group contains:
+      - `atomic_numbers`: Atomic numbers of the atoms.
+      - `formal_charges`: Formal charges of the atoms.
+      - Datasets for multiple conformations directly, without individual conformation groups.
+
+    Each conformation group (version 1.0) or molecule group (version 2.0) should have the following datasets:
+    - `positions`: Atomic positions. Units: Angstrom.
+    - `forces`: Forces on the atoms. Units: eV/Å.
+    - `partial_charges`: Atomic partial charges. Units: electron charges.
+    - `dipole_moment`: Molecule's dipole moment. Units: e*Å.
+    - `formation_energy` (version 1.0) or `formation_energies` (version 2.0): Formation energy. Units: eV.
+    Each dataset should also have an `units` attribute specifying its units (i.e., `Å`, `eV`, `e*Å`).
+
+    Args:
+        root (string, optional): Root directory where the dataset should be saved.
+        transform (callable, optional): A function/transform that takes in an :obj:`torch_geometric.data.Data` object and returns a transformed version.
+        pre_transform (callable, optional): A function/transform that takes in an :obj:`torch_geometric.data.Data` object and returns a transformed version.
+        pre_filter (callable, optional): A function that takes in an :obj:`torch_geometric.data.Data` object and returns a boolean value, indicating whether the data object should be included in the final dataset.
+        paths (string or list): Path to the HDF5 files or directory containing the HDF5 files.
+        max_gradient (float, optional): Maximum gradient norm. Samples with larger gradients are discarded.
+        subsample_molecules (int, optional): Subsample molecules. Only every `subsample_molecules` molecule is used.
+
+    Examples::
+        >>> import numpy as np
+        >>> from torchmdnet.datasets import Ace
+        >>> import h5py
+        >>>
+        >>> with h5py.File("molecule.h5", 'w') as f:
+        ...     f.attrs["layout"] = "Ace"
+        ...     f.attrs["layout_version"] = "1.0"
+        ...     f.attrs["name"] = "sample_molecule_data"
+        ...     for m in range(3):  # Three molecules
+        ...         mol = f.create_group(f"mol_{m+1}")
+        ...         mol["atomic_numbers"] = [1, 6, 8]  # H, C, O
+        ...         mol["formal_charges"] = [0, 0, 0]  # Neutral charges
+        ...         confs = mol.create_group("conformations")
+        ...         for i in range(2):  # Two conformations
+        ...             conf = confs.create_group(f"conf_{i+1}")
+        ...             conf["positions"] = np.random.random((3, 3))
+        ...             conf["positions"].attrs["units"] = "Å"
+        ...             conf["formation_energy"] = np.random.random()
+        ...             conf["formation_energy"].attrs["units"] = "eV"
+        ...             conf["forces"] = np.random.random((3, 3))
+        ...             conf["forces"].attrs["units"] = "eV/Å"
+        ...             conf["partial_charges"] = np.random.random(3)
+        ...             conf["partial_charges"].attrs["units"] = "e"
+        ...             conf["dipole_moment"] = np.random.random(3)
+        ...             conf["dipole_moment"].attrs["units"] = "e*Å"
+        >>> dataset = Ace(root=".", paths="molecule.h5")
+        >>> len(dataset)
+        6
+        >>> dataset = Ace(root=".", paths=["molecule.h5", "molecule.h5"])
+        >>> len(dataset)
+        12
+    """
+
     def __init__(
         self,
         root=None,
@@ -305,7 +380,22 @@ def len(self):
         return len(self.y_mm)
 
     def get(self, idx):
-
+        """Gets the data object at index :obj:`idx`.
+        The data object contains the following attributes:
+            - :obj:`z`: Atomic numbers of the atoms.
+            - :obj:`pos`: Positions of the atoms.
+            - :obj:`y`: Formation energy of the molecule.
+            - :obj:`neg_dy`: Forces on the atoms.
+            - :obj:`q`: Total charge of the molecule.
+            - :obj:`pq`: Partial charges of the atoms.
+            - :obj:`dp`: Dipole moment of the molecule.
+
+        Args:
+            idx (int): Index of the data object.
+
+        Returns:
+            :obj:`torch_geometric.data.Data`: The data object.
+        """
         atoms = slice(self.idx_mm[idx], self.idx_mm[idx + 1])
         z = pt.tensor(self.z_mm[atoms], dtype=pt.long)
         pos = pt.tensor(self.pos_mm[atoms], dtype=pt.float32)