Elastic Tensors#
Let’s do something more interesting that normally takes quite a bit of work in DFT: calculating an elastic constant! Elastic properties are important to understand how strong or easy to deform a material is, or how a material might change if compressed or expanded in specific directions (i.e. the Poisson ratio!).
We don’t have to change much code from above, we just use a built-in recipe to calculate the elastic tensor from quacc. This recipe
(optionally) Relaxes the unit cell using the MLIP
Generates a number of deformed unit cells by applying strains
For each deformation, a relaxation using the MLIP and (optionally) a single point calculation is run
Finally, all of the above calculations are used to calculate the elastic properties of the material
For more documentation, see the quacc docs for quacc.recipes.mlp.elastic_tensor_flow
Need to install fairchem-core or get UMA access or getting permissions/401 errors?
Install the necessary packages using pip, uv etc
Get access to any necessary huggingface gated models
Get and login to your Huggingface account
Request access to https://huggingface.co/facebook/UMA
Create a Huggingface token at https://huggingface.co/settings/tokens/ with the permission “Permissions: Read access to contents of all public gated repos you can access”
Add the token as an environment variable using
huggingface-cli loginor by setting the HF_TOKEN environment variable.
from __future__ import annotations
from ase.build import bulk
from quacc.recipes.mlp.elastic import elastic_tensor_flow
# Make an Atoms object of a bulk Cu structure
atoms = bulk("Cu")
# Run an elastic property calculation with our favorite MLP potential
result = elastic_tensor_flow(
atoms,
job_params={
"all": dict(
method="fairchem",
name_or_path="uma-s-1p1",
task_name="omat",
),
},
)
WARNING:root:device was not explicitly set, using device='cuda'.
/home/runner/work/_tool/Python/3.12.12/x64/lib/python3.12/site-packages/pydantic/_internal/_generate_schema.py:2249: UnsupportedFieldAttributeWarning: The 'repr' attribute with value False was provided to the `Field()` function, which has no effect in the context it was used. 'repr' is field-specific metadata, and can only be attached to a model field using `Annotated` metadata or by assignment. This may have happened because an `Annotated` type alias using the `type` statement was used, or if the `Field()` function was attached to a single member of a union type.
warnings.warn(
/home/runner/work/_tool/Python/3.12.12/x64/lib/python3.12/site-packages/pydantic/_internal/_generate_schema.py:2249: UnsupportedFieldAttributeWarning: The 'frozen' attribute with value True was provided to the `Field()` function, which has no effect in the context it was used. 'frozen' is field-specific metadata, and can only be attached to a model field using `Annotated` metadata or by assignment. This may have happened because an `Annotated` type alias using the `type` statement was used, or if the `Field()` function was attached to a single member of a union type.
warnings.warn(
WARNING:root:The 'seed' argument is deprecated and will be removed in future versions. Please set the seed in the MLIPPredictUnit configuration instead.
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-50-245505-59941
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-50-245505-59941
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-51-053899-53545
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-51-053899-53545
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-51-169922-40240
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-51-169922-40240
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-51-284543-31762
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-51-284543-31762
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-51-398487-60545
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-51-398487-60545
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-51-512325-85751
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-51-512325-85751
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-51-626064-47153
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-51-626064-47153
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-51-739840-82490
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-51-739840-82490
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-51-855731-46278
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-51-855731-46278
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-51-970001-60271
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-51-970001-60271
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-52-083848-85553
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-52-083848-85553
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-52-197781-11222
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-52-197781-11222
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-52-311619-42646
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-52-311619-42646
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-52-424676-96714
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-52-424676-96714
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-52-527265-12403
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-52-527265-12403
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-52-632297-67592
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-52-632297-67592
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-52-737621-30322
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-52-737621-30322
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-52-844612-29639
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-52-844612-29639
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-52-947567-51796
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-52-947567-51796
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-53-052748-31955
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-53-052748-31955
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-53-158174-43752
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-53-158174-43752
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-53-261521-95806
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-53-261521-95806
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-53-364273-91366
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-53-364273-91366
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-53-469478-86518
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-53-469478-86518
INFO:quacc.runners.prep:Calculation will run at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/tmp-quacc-2025-10-12-17-48-53-575292-17798
INFO:quacc.runners.prep:Calculation results stored at /home/runner/work/fairchem/fairchem/docs/inorganic_materials/examples_tutorials/quacc-2025-10-12-17-48-53-575292-17798
result["elasticity_doc"].bulk_modulus
BulkModulus(voigt=154.385, reuss=154.385, vrh=154.385)
Congratulations, you ran your first elastic tensor calculation!