Merge pull request #360 from pyiron/import_atomistics

Import atomistics

.ci_support/environment-notebooks-integration.yml

@@ -2,6 +2,7 @@ channels:
 - conda-forge
 dependencies:
 - ase =3.22.1
+- atomistics =0.1.32
 - coveralls
 - codacy-coverage
 - damask =3.0.0b

.ci_support/environment-pypi-unit.yml

@@ -2,6 +2,7 @@ channels:
 - conda-forge
 dependencies:
 - coveralls
+- atomistics =0.1.32
 - coverage
 - codacy-coverage
 - matplotlib =3.9.2

pyiron_continuum/reference/elastic_constants.py

@@ -0,0 +1,27 @@
+# coding: utf-8
+# Copyright (c) Max-Planck-Institut für Eisenforschung GmbH - Computational Materials Design (CM) Department
+# Distributed under the terms of "New BSD License", see the LICENSE file.
+
+
+from atomistics.referencedata.wikipedia import get_elastic_properties
+
+
+def get_elastic_constants(chemical_symbol):
+    """
+    Get the elastic tensor of a material from the wikipedia database.
+
+    Args:
+        chemical_symbol (str): Chemical symbol of the element.
+
+    Returns:
+        dict: Dictionary with the elastic tensor of the material (isotropic).
+    """
+    d = get_elastic_properties(chemical_symbol)
+    G = d["shear_modulus"]
+    v = d["poissons_ratio"]
+    E = d["youngs_modulus"]
+    C_11 = E * (1 - v) / (1 + v) / (1 - 2 * v)
+    C_12 = E * v / (1 + v) / (1 - 2 * v)
+    C_44 = G
+    d.update({"C_11": C_11, "C_12": C_12, "C_44": C_44})
+    return d

tests/unit/reference/test_elastic_constants.py

@@ -0,0 +1,20 @@
+# coding: utf-8
+# Copyright (c) Max-Planck-Institut für Eisenforschung GmbH - Computational Materials Design (CM) Department
+# Distributed under the terms of "New BSD License", see the LICENSE file.
+
+import unittest
+from pyiron_continuum.reference.elastic_constants import get_elastic_constants
+import numpy as np
+
+
+class TestDecorators(unittest.TestCase):
+    def test_elastic_constants(self):
+        d = get_elastic_constants("Fe")
+        self.assertTrue(all(key in d for key in ["C_11", "C_12", "C_44"]))
+        for value in d.values():
+            self.assertTrue(np.isscalar(value))
+            self.assertGreater(value, 0)
+
+
+if __name__ == "__main__":
+    unittest.main()