Standard model outputs

In order for multiple simulation engines to be able to exploit atomic properties computing by arbitrary metatensor atomistic models, we need all the models to return data with specific metadata. If your model returns one of the output defined in this documentation, then the model should follow the metadata structure described here.

For other kind of output, you are free to use any relevant metadata structure, but if multiple people are producing the same kind of outputs, they are encouraged to come together, define the metadata they need and add a new section to this page.

Energy

Energy (and its gradients: forces/virial) is associated with the "energy" key in the model outputs, and must have the following metadata:

• keys: the energy keys must have a single dimension named "_", with a single entry set to 0. The energy is always a single block metatensor.torch.TensorMap.

• samples: if doing per_atom output, the sample names must be ["system", "atom"], otherwise the sample names must be ["system"]. "structure" must range from 0 to the number of systems given as input to the model. "atom" must range between 0 and the number of atoms in the corresponding system. If selected_atoms is provided, then only the selected atoms for each system should be part of the samples.

• components: the energy must not have any components.

• properties: the energy must have a single property dimension named "energy", with a single entry set to 0.