diff --git a/emmet-core/emmet/core/xrd.py b/emmet-core/emmet/core/xrd.py
new file mode 100644
index 0000000000..bff2e76e6b
--- /dev/null
+++ b/emmet-core/emmet/core/xrd.py
@@ -0,0 +1,112 @@
+from enum import Enum
+from typing import Dict, List, Optional, Tuple
+
+import numpy as np
+from pydantic import BaseModel, Field, root_validator
+from pymatgen.analysis.diffraction.xrd import WAVELENGTHS, XRDCalculator
+from pymatgen.core.periodic_table import Element
+
+from emmet.core.spectrum import SpectrumDoc
+from emmet.core.utils import ValueEnum, jsanitize
+from emmet.stubs import DiffractionPattern, Structure
+
+
+class Edge(ValueEnum):
+    K_Alpha = "Ka"
+    K_Alpha1 = "Ka1"
+    K_Alpha2 = "Ka2"
+    K_Beta = "Kb"
+    K_Beta1 = "Kb1"
+    K_Beta2 = "Kb2"
+
+
+class XRDDoc(SpectrumDoc):
+    """
+    Document describing a XRD Diffraction Pattern
+    """
+
+    spectrum: DiffractionPattern
+    min_two_theta: float
+    max_two_theta: float
+    wavelength: float = Field(..., description="Wavelength for the diffraction source")
+    target: Element = Field(
+        None, description="Target element for the diffraction source"
+    )
+    edge: Edge = Field(None, description="Atomic edge for the diffraction source")
+
+    @root_validator(pre=True)
+    def get_target_and_edge(cls, values: Dict):
+        print("Validations")
+        # Only do this if neither target not edge is defined
+        if "target" not in values and "edge" not in values:
+            print("Are we even getting here?")
+            try:
+                pymatgen_wavelength = next(
+                    k
+                    for k, v in WAVELENGTHS.items()
+                    if np.allclose(values["wavelength"], v)
+                )
+                values["target"] = pymatgen_wavelength[:2]
+                values["edge"] = pymatgen_wavelength[2:]
+
+            except Exception:
+                return values
+        return values
+
+    @classmethod
+    def from_structure(
+        cls,
+        material_id: str,
+        spectrum_id: str,
+        structure: Structure,
+        wavelength: float,
+        min_two_theta=0,
+        max_two_theta=180,
+        symprec=0.1,
+        **kwargs,
+    ) -> "XRDDoc":
+        calc = XRDCalculator(wavelength=wavelength, symprec=symprec)
+        pattern = calc.get_pattern(
+            structure, two_theta_range=(min_two_theta, max_two_theta)
+        )
+
+        return super().from_structure(
+            material_id=material_id,
+            spectrum_id=spectrum_id,
+            structure=structure,
+            spectrum=pattern,
+            wavelength=wavelength,
+            min_two_theta=min_two_theta,
+            max_two_theta=max_two_theta,
+            **kwargs,
+        )
+
+    @classmethod
+    def from_target(
+        cls,
+        material_id: str,
+        structure: Structure,
+        target: Element,
+        edge: Edge,
+        min_two_theta=0,
+        max_two_theta=180,
+        symprec=0.1,
+        **kwargs,
+    ) -> "XRDDoc":
+        if f"{target}{edge}" not in WAVELENGTHS:
+            raise ValueError(f"{target}{edge} not in pymatgen wavelenghts dictionarty")
+
+        wavelength = WAVELENGTHS[f"{target}{edge}"]
+        spectrum_id = f"{material_id}-{target}{edge}"
+
+        return cls.from_structure(
+            material_id=material_id,
+            spectrum_id=spectrum_id,
+            structure=structure,
+            wavelength=wavelength,
+            target=target,
+            edge=edge,
+            min_two_theta=min_two_theta,
+            max_two_theta=max_two_theta,
+            **kwargs,
+        )