add a placeholder MolecularOrbitalsState

src/nomad_simulations/schema_packages/atoms_state.py

@@ -641,3 +641,72 @@ def normalize(self, archive: 'EntryArchive', logger: 'BoundLogger') -> None:
             self.chemical_symbol = self.resolve_chemical_symbol(logger=logger)
         if self.atomic_number is None:
             self.atomic_number = self.resolve_atomic_number(logger=logger)
+
+
+class MolecularOrbitalsState(Entity):
+    """
+    A base section to define molecular orbitals.
+    """
+
+    symmetry_label = Quantity(
+        type=str,
+        description="""
+        Symmetry label of the molecular orbital (e.g., 'sigma', 'pi', 'delta').
+        """,
+    )
+
+    energy = Quantity(
+        type=np.float64,
+        #unit='eV',
+        description="""
+        Energy of the molecular orbital.
+        """,
+    )
+
+    occupation = Quantity(
+        type=np.float64,
+        description="""
+        Occupation of the molecular orbital. This value is typically an integer (0 or 2)
+        in closed-shell systems, but can be fractional in open-shell or spin-polarized
+        calculations.
+        """,
+    )
+
+    spin = Quantity(
+        type=MEnum('alpha', 'beta'),
+        description="""
+        Spin of the molecular orbital. 'alpha' corresponds to spin-up, 'beta' corresponds
+        to spin-down.
+        """,
+    )
+
+    coefficients = Quantity(
+        type=np.float64,
+        shape=['number_of_atoms', 'number_of_basis_functions'],
+        description="""
+        Coefficients of the molecular orbital expressed as a linear combination of atomic orbitals.
+        The shape corresponds to the number of atoms and their associated basis functions.
+        """,
+    )
+
+    atom_contributions = SubSection(
+        sub_section=AtomsState.m_def,
+        repeats=True,
+        description="""
+        Contribution of each atom to the molecular orbital, as defined by its basis functions.
+        """,
+    )
+
+    def normalize(self, archive: 'EntryArchive', logger: 'BoundLogger') -> None:
+        super().normalize(archive, logger)
+
+        # Validation: Ensure occupation values are consistent
+        if self.occupation is not None and (self.occupation < 0 or self.occupation > 2):
+            logger.error("The molecular orbital occupation must be between 0 and 2.")
+
+        # Validation: Ensure coefficients are provided if atom contributions are defined
+        if self.atom_contributions and self.coefficients is None:
+            logger.error(
+                "Coefficients must be defined when atom contributions are provided."
+            )
+

src/nomad_simulations/schema_packages/model_method.py

@@ -1223,31 +1223,6 @@ def normalize(self, archive: 'EntryArchive', logger: 'BoundLogger') -> None:
         super().normalize(archive, logger)
 
 
-class BaseMolecularOrbital(ArchiveSection):
-    """
-    A section representing a single molecular orbital.
-    """
-
-    energy = Quantity(
-        type=np.float64,
-        # unit='electron_volt',
-        description='Energy of the molecular orbital.',
-    )
-
-    occupation = Quantity(
-        type=np.float64, description='Occupation number of the molecular orbital.'
-    )
-
-    symmetry_label = Quantity(
-        type=str, description='Symmetry label of the molecular orbital.'
-    )
-
-    orbital_ref = SubSection(
-        sub_section=OrbitalsState.m_def,
-        description='Reference to the underlying atomic orbital state.',
-    )
-
-
 class MolecularOrbitals(ArchiveSection):
     """
     A section for molecular orbital schemes used in quantum chemistry calculations.
@@ -1268,18 +1243,6 @@ class MolecularOrbitals(ArchiveSection):
         a_eln=ELNAnnotation(component='EnumEditQuantity'),
     )
 
-    orbital_set = Quantity(
-        type=MEnum('canonical', 'natural', 'localized'),
-        description="""
-        Specifies the type of orbitals used in the molecular orbital scheme:
-        - canonical: Default canonical molecular orbitals.
-        - natural: Natural orbitals obtained from the density matrix.
-        - localized: Localized orbitals such as Boys or Foster-Boys localization.
-        TODO: this will be later connected to MCSCF.
-        """,
-        a_eln=ELNAnnotation(component='EnumEditQuantity'),
-    )
-
     n_alpha_electrons = Quantity(
         type=np.int32,
         description="""
@@ -1301,16 +1264,16 @@ class MolecularOrbitals(ArchiveSection):
         """,
     )
 
-    molecular_orbitals = SubSection(
-        sub_section=BaseMolecularOrbital.m_def,
-        repeats=True,
-        description="""
-        Detailed information about each molecular orbital,
-        including energy, occupation, and symmetry label.
-        """,
-    )
+    # molecular_orbitals = SubSection(
+    #     sub_section=BaseMolecularOrbital.m_def,
+    #     repeats=True,
+    #     description="""
+    #     Detailed information about each molecular orbital,
+    #     including energy, occupation, and symmetry label.
+    #     """,
+    # )
 
-    total_spin = Quantity(
+    sz_projection = Quantity(
         type=np.float64,
         description="""
         Total spin of the system defined as S = (n_alpha_electrons - n_beta_electrons) / 2.
@@ -1364,24 +1327,8 @@ def normalize(self, archive: 'EntryArchive', logger: 'BoundLogger') -> None:
         if not self.validate_scheme(logger):
             logger.error('Invalid molecular orbital scheme.')
 
-        # Resolve the number of molecular orbitals
-        if self.n_molecular_orbitals is None and self.molecular_orbitals:
-            self.n_molecular_orbitals = len(self.molecular_orbitals)
-
-        # Validate molecular orbital occupation
-        total_occupation = sum(
-            orbital.occupation
-            for orbital in self.molecular_orbitals
-            if orbital.occupation is not None
-        )
-        expected_occupation = self.n_alpha_electrons + self.n_beta_electrons
-        if total_occupation != expected_occupation:
-            logger.warning(
-                f'The total occupation ({total_occupation}) does not match the expected value ({expected_occupation}).'
-            )
-
 
-class GTOIntegralDecomposition(BaseModelMethod):
+class IntegralDecomposition(BaseModelMethod):
     """
     A general class for integral decomposition techniques for Coulomb and exchange integrals to speed up the calculation.
     Examples:
@@ -1463,16 +1410,20 @@ class LocalCorrelation(ArchiveSection):
     """
 
     type = Quantity(
-        type=MEnum('PNO', 'domain'),
+        type=MEnum('PNO', 'LPNO', 'DLPNO'),
         description="""
         the type of local correlation.
         """,
     )
 
     ansatz = Quantity(
-        type=MEnum('LMP2', 'LCC', 'LocalDFT'),
+        type=MEnum('MP2', 'CC', 'DH-DFT'),
         description="""
         The underlying ansatz for the local correlation treatment.
+        LMP2
+        LCC
+        DH-DFT: double-hybrid DFT
+        ...
         """,
     )
 
@@ -1493,6 +1444,7 @@ class CoupledCluster(ModelMethodElectronic):
         a_eln=ELNAnnotation(component='StringEditQuantity'),
     )
 
+    # add a real reference determinant reference
     reference_determinant = Quantity(
         type=MEnum('UHF', 'RHF', 'ROHF', 'UKS', 'RKS', 'ROKS'),
         description="""