diff --git a/src/nomad_simulations/outputs.py b/src/nomad_simulations/outputs.py
index 42fd2035..c9aef22e 100644
--- a/src/nomad_simulations/outputs.py
+++ b/src/nomad_simulations/outputs.py
@@ -41,7 +41,8 @@
     AbsorptionSpectrum,
     XASSpectrum,
     Permittivity,
-    TotalEnergy
+    TotalEnergy,
+    TotalForce,
 )
 
 
@@ -112,7 +113,9 @@ class Outputs(ArchiveSection):
 
     xas_spectra = SubSection(sub_section=XASSpectrum.m_def, repeats=True)
 
-    total_energy = SubSection(SubSection=TotalEnergy.m_def, repeats=True)
+    total_energy = SubSection(sub_section=TotalEnergy.m_def, repeats=True)
+
+    total_force = SubSection(sub_section=TotalForce.m_def, repeats=True)
 
     # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
     # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
@@ -296,6 +299,7 @@ def normalize(self, archive, logger) -> None:
                     logger=logger,
                 )
 
+
 class WorkflowOutputs(Outputs):
     """
     This section contains output properties that depend on a single system, but were
@@ -320,6 +324,7 @@ class WorkflowOutputs(Outputs):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class TrajectoryOutputs(WorkflowOutputs):
     """
     This section contains output properties that depend on a single system, but were
@@ -328,6 +333,7 @@ class TrajectoryOutputs(WorkflowOutputs):
 
     time = Quantity(
         type=np.float64,
+        unit='ps',
         description="""
         The elapsed simulated physical time since the start of the trajectory.
         """,
diff --git a/src/nomad_simulations/physical_property.py b/src/nomad_simulations/physical_property.py
index e879a593..39c1d926 100644
--- a/src/nomad_simulations/physical_property.py
+++ b/src/nomad_simulations/physical_property.py
@@ -320,4 +320,4 @@ def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
         # Resolve if the physical property `is_derived` or not from another physical property.
-        self.is_derived = self._is_derived()
\ No newline at end of file
+        self.is_derived = self._is_derived()
diff --git a/src/nomad_simulations/properties/__init__.py b/src/nomad_simulations/properties/__init__.py
index a8834033..0146ca18 100644
--- a/src/nomad_simulations/properties/__init__.py
+++ b/src/nomad_simulations/properties/__init__.py
@@ -23,6 +23,7 @@
     ClassicalEnergyContributions,
     QuantumEnergyContributions,
 )
+from .forces import TotalForce, ForceContributions
 from .band_gap import ElectronicBandGap
 from .spectral_profile import (
     SpectralProfile,
diff --git a/src/nomad_simulations/properties/energies.py b/src/nomad_simulations/properties/energies.py
index d7d4c4b3..9b7f2fe0 100644
--- a/src/nomad_simulations/properties/energies.py
+++ b/src/nomad_simulations/properties/energies.py
@@ -19,9 +19,11 @@
 import numpy as np
 
 from nomad.metainfo import Quantity, Section, Context, SubSection, MEnum
+from nomad.datamodel.data import ArchiveSection
 
 from nomad_simulations.physical_property import PhysicalProperty
 
+
 class FermiLevel(PhysicalProperty):
     """
     Energy required to add or extract a charge from a material at zero temperature. It can be also defined as the chemical potential at zero temperature.
@@ -82,6 +84,7 @@ def normalize(self, archive, logger) -> None:
 # List of classical energy contribuions
 ####################################################
 
+
 class PotentialEnergy(PhysicalProperty):
     """
     Section containing the potential energy of a (sub)system.
@@ -98,6 +101,7 @@ class PotentialEnergy(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class KineticEnergy(PhysicalProperty):
     """
     Section containing the kinetic energy of a (sub)system.
@@ -152,6 +156,7 @@ class VDWEnergy(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class ElectrostaticEnergy(PhysicalProperty):
     """
     Section containing all electrostatic contributions to the potential energy of a (sub)system.
@@ -168,6 +173,7 @@ class ElectrostaticEnergy(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class ElectrostaticShortRangeEnergy(PhysicalProperty):
     """
     Section containing short-range electrostatic contributions to the potential energy of a (sub)system.
@@ -184,6 +190,7 @@ class ElectrostaticShortRangeEnergy(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class ElectrostaticLongRangeEnergy(PhysicalProperty):
     """
     Section containing long-range electrostatic contributions to the potential energy of a (sub)system.
@@ -200,6 +207,7 @@ class ElectrostaticLongRangeEnergy(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class BondedEnergy(PhysicalProperty):
     """
     Section containing all bonded (i.e., intramolecular) contributions to the potential energy of a (sub)system.
@@ -216,6 +224,7 @@ class BondedEnergy(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class BondEnergy(PhysicalProperty):
     """
     Section containing contributions to the potential energy from bond interactions of a (sub)system.
@@ -232,6 +241,7 @@ class BondEnergy(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class AngleEnergy(PhysicalProperty):
     """
     Section containing contributions to the potential energy from angle interactions of a (sub)system.
@@ -248,6 +258,7 @@ class AngleEnergy(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class DihedralEnergy(PhysicalProperty):
     """
     Section containing contributions to the potential energy from dihedral interactions of a (sub)system.
@@ -264,6 +275,7 @@ class DihedralEnergy(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class ImproperDihedralEnergy(PhysicalProperty):
     """
     Section containing contributions to the potential energy from improper dihedral interactions of a (sub)system.
@@ -280,6 +292,7 @@ class ImproperDihedralEnergy(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class ExternalEnergy(PhysicalProperty):
     """
     Section containing contributions to the potential energy from external interactions of a (sub)system.
@@ -296,6 +309,7 @@ class ExternalEnergy(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class ClassicalEnergyContributions(ArchiveSection):
     """
     Section containing contributions to the potential energy from a classical force field.
@@ -309,9 +323,13 @@ class ClassicalEnergyContributions(ArchiveSection):
 
     electrostatic = SubSection(sub_section=ElectrostaticEnergy.m_def, repeats=False)
 
-    electrostatic_short_range = SubSection(sub_section=ElectrostaticShortRangeEnergy.m_def, repeats=False)
+    electrostatic_short_range = SubSection(
+        sub_section=ElectrostaticShortRangeEnergy.m_def, repeats=False
+    )
 
-    electrostatic_long_range = SubSection(sub_section=ElectrostaticLongRangeEnergy.m_def, repeats=False)
+    electrostatic_long_range = SubSection(
+        sub_section=ElectrostaticLongRangeEnergy.m_def, repeats=False
+    )
 
     bonded = SubSection(sub_section=BondedEnergy.m_def, repeats=False)
 
@@ -321,7 +339,9 @@ class ClassicalEnergyContributions(ArchiveSection):
 
     dihedral = SubSection(sub_section=DihedralEnergy.m_def, repeats=False)
 
-    improper_dihedral = SubSection(sub_section=ImproperDihedralEnergy.m_def, repeats=False)
+    improper_dihedral = SubSection(
+        sub_section=ImproperDihedralEnergy.m_def, repeats=False
+    )
 
     external = SubSection(sub_section=ExternalEnergy.m_def, repeats=False)
 
@@ -330,10 +350,12 @@ def normalize(self, archive, logger) -> None:
         # Set the name of the section
         self.name = self.m_def.name
 
+
 ######################################
 # List of quantum energy contributions
 ######################################
 
+
 class ElectronicEnergy(PhysicalProperty):
     """
     Section containing the electronic energy of a (sub)system.
@@ -347,12 +369,11 @@ class ElectronicEnergy(PhysicalProperty):
         """,
     )
 
-    contributions = SubSection(sub_section=EnergyContributions.m_def, repeats=True)
-
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
         allowed_contributions = ['PotKin']
 
+
 class ElectronicKineticEnergy(PhysicalProperty):
     """
     Section containing the electronic kinetic energy of a (sub)system.
@@ -369,11 +390,13 @@ class ElectronicKineticEnergy(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class XCEnergy(PhysicalProperty):
     """
     Section containing the exchange-correlation (XC) energy of a (sub)system,
     calculated using the functional stored in XC_functional.
     """
+
     # ! Someone check this description!
     # ? Do we really want to specify the method here? This can't be user-defined?
 
@@ -388,6 +411,7 @@ class XCEnergy(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class XCPotentialEnergy(PhysicalProperty):
     """
     Section containing the potential energy contribution to the exchange-correlation (XC) energy,
@@ -396,6 +420,7 @@ class XCPotentialEnergy(PhysicalProperty):
         of XC that is in the sum of the eigenvalues. Value associated with the
         configuration, should be the most converged value.          |
     """
+
     # ! Someone check this description!
     # ? Do we really want to specify the method here? This can't be user-defined?
 
@@ -410,12 +435,14 @@ class XCPotentialEnergy(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 # ? XCCorrelationEnergy?
 class CorrelationEnergy(PhysicalProperty):
     """
     Section containing the correlation energy of a (sub)system,
     calculated using the method described in XC_functional.
     """
+
     # ! Someone check this description!
     # ? Do we really want to specify the method here? This can't be user-defined?
 
@@ -430,12 +457,14 @@ class CorrelationEnergy(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 # ? XCExchangeEnergy?
 class ExchangeEnergy(PhysicalProperty):
     """
     Section containing the exchange energy of a (sub)system,
     calculated using the method described in XC_functional.
     """
+
     # ! Someone check this description!
     # ? Do we really want to specify the method here? This can't be user-defined?
 
@@ -468,11 +497,13 @@ class ZeroTemperatureEnergy(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class ZeroPointEnergy(PhysicalProperty):
     """
     Section containing the zero-point vibrational energy of a (sub)system,
     calculated using the method described in zero_point_method.
     """
+
     # ! Someone check this description!
     # ? Do we really want to specify the method here? This can't be user-defined?
 
@@ -487,6 +518,7 @@ class ZeroPointEnergy(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class ElectrostaticEnergy(PhysicalProperty):
     """
     Section containing the electrostatic energy (nuclei + electrons) of a (sub)system.
@@ -503,6 +535,7 @@ class ElectrostaticEnergy(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class NuclearRepulsionEnergy(PhysicalProperty):
     """
     Section containing the nuclear-nuclear repulsion energy of a (sub)system.
@@ -524,11 +557,14 @@ class QuantumEnergyContributions(ArchiveSection):
     """
     Section containing contributions to the potential energy from a DFT calculation.
     """
-...
+
+    ...
 
     electronic = SubSection(sub_section=ElectronicEnergy.m_def, repeats=False)
 
-    electronic_kinetic = SubSection(sub_section=ElectronicKineticEnergy.m_def, repeats=False)
+    electronic_kinetic = SubSection(
+        sub_section=ElectronicKineticEnergy.m_def, repeats=False
+    )
 
     xc = SubSection(sub_section=XCEnergy.m_def, repeats=False)
 
@@ -538,18 +574,24 @@ class QuantumEnergyContributions(ArchiveSection):
 
     exchange = SubSection(sub_section=ExchangeEnergy.m_def, repeats=False)
 
-    zero_temperature = SubSection(sub_section=ZeroTemperatureEnergy.m_def, repeats=False)
+    zero_temperature = SubSection(
+        sub_section=ZeroTemperatureEnergy.m_def, repeats=False
+    )
 
     zero_point = SubSection(sub_section=ZeroPointEnergy.m_def, repeats=False)
 
     electrostatic = SubSection(sub_section=ElectrostaticEnergy.m_def, repeats=False)
 
-    nuclear_repulsion = SubSection(sub_section=NuclearRepulsionEnergy.m_def, repeats=False)
+    nuclear_repulsion = SubSection(
+        sub_section=NuclearRepulsionEnergy.m_def, repeats=False
+    )
+
 
 ##########################
 # Other / General energies
 ##########################
 
+
 class TotalEnergy(PhysicalProperty):
     """
     Section containing the total energy of a (sub)system.
@@ -564,12 +606,17 @@ class TotalEnergy(PhysicalProperty):
     )
     # ? Do we need these descriptions under value? It ends up simply duplicating the section info to some extent.
 
-    classical_contributions = SubSection(sub_section=ClassicalEnergyContributions.m_def, repeats=False)
+    classical_contributions = SubSection(
+        sub_section=ClassicalEnergyContributions.m_def, repeats=False
+    )
 
-    quantum_contributions = SubSection(sub_section=QuantumEnergyContributions.m_def, repeats=False)
+    quantum_contributions = SubSection(
+        sub_section=QuantumEnergyContributions.m_def, repeats=False
+    )
 
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
+        #? Should we set total energy value as sum of all contributions if not set explicitly?
 
     # madelung = SubSection(
     #     sub_section=EnergyEntry.m_def,
@@ -709,7 +756,6 @@ def normalize(self, archive, logger) -> None:
     #     """,
     # )
 
-
     # # TODO this should be removed and replaced by correction in EnergyEntry
     # current = SubSection(
     #     sub_section=EnergyEntry.m_def,
@@ -723,8 +769,6 @@ def normalize(self, archive, logger) -> None:
     # )
 
 
-
-
 # # ? Do we want to allow this?
 # class EnergyCustom(PhysicalProperty):
 #     """
diff --git a/src/nomad_simulations/properties/forces.py b/src/nomad_simulations/properties/forces.py
index 71721933..11676584 100644
--- a/src/nomad_simulations/properties/forces.py
+++ b/src/nomad_simulations/properties/forces.py
@@ -34,45 +34,19 @@
 # limitations under the License.
 #
 
-import re
 import numpy as np
 
-from nomad.units import ureg
+from nomad.metainfo import Quantity, Section, Context, SubSection, MEnum
 from nomad.datamodel.data import ArchiveSection
-from nomad.metainfo import Quantity, SubSection, SectionProxy, MEnum
-from nomad.metainfo.metainfo import DirectQuantity, Dimension
-from nomad.datamodel.metainfo.annotations import ELNAnnotation
-
-from .outputs import Outputs, SCFOutputs, WorkflowOutputs, TrajectoryOutputs
-from .atoms_state import AtomsState
-from .physical_property import PhysicalProperty
-
-
-from nomad.datamodel.metainfo.common import (
-    FastAccess,
-    PropertySection,
-    ProvenanceTracker,
-)
-from nomad.metainfo import (
-    Category,
-    HDF5Reference,
-    MCategory,
-    MEnum,
-    MSection,
-    Package,
-    Quantity,
-    Reference,
-    Section,
-    SectionProxy,
-    SubSection,
-)
-
-from .model_system import ModelSystem
+
+from nomad_simulations.physical_property import PhysicalProperty
+
 
 ################################
 # List of Forces Contributions #
 ################################
 
+
 class FreeForce(PhysicalProperty):
     """
     Contains the value and information regarding the forces on the atoms
@@ -94,6 +68,7 @@ class FreeForce(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class ZeroTemperatureForce(PhysicalProperty):
     """
     Contains the value and information regarding the forces on the atoms
@@ -112,9 +87,9 @@ class ZeroTemperatureForce(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class RawForce(PhysicalProperty):
-    """
-    """
+    """ """
 
     value = Quantity(
         type=np.dtype(np.float64),
@@ -130,8 +105,7 @@ class RawForce(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
-
-    #? Do we want to support custom contributions?
+    # ? Do we want to support custom contributions?
     # contributions = SubSection(
     #     sub_section=ForcesEntry.m_def,
     #     description="""
@@ -149,6 +123,7 @@ def normalize(self, archive, logger) -> None:
     #     repeats=True,
     # )
 
+
 class ForceContributions(ArchiveSection):
     """
     Section containing contributions to the potential energy from a classical force field.
@@ -156,7 +131,9 @@ class ForceContributions(ArchiveSection):
 
     free = SubSection(sub_section=FreeForce.m_def, repeats=False)
 
-    zero_temperature_force = SubSection(sub_section=ZeroTemperatureForce.m_def, repeats=False)
+    zero_temperature_force = SubSection(
+        sub_section=ZeroTemperatureForce.m_def, repeats=False
+    )
 
     raw = SubSection(sub_section=RawForce.m_def, repeats=False)
 
@@ -166,12 +143,12 @@ def normalize(self, archive, logger) -> None:
 
 
 # Old version of the Forces description
-        # Value of the forces acting on the atoms. This is calculated as minus gradient of
-        # the corresponding energy type or contribution **including** constraints, if
-        # present. The derivatives with respect to displacements of nuclei are evaluated in
-        # Cartesian coordinates.  In addition, these are obtained by filtering out the
-        # unitary transformations (center-of-mass translations and rigid rotations for
-        # non-periodic systems, see value_raw for the unfiltered counterpart).
+# Value of the forces acting on the atoms. This is calculated as minus gradient of
+# the corresponding energy type or contribution **including** constraints, if
+# present. The derivatives with respect to displacements of nuclei are evaluated in
+# Cartesian coordinates.  In addition, these are obtained by filtering out the
+# unitary transformations (center-of-mass translations and rigid rotations for
+# non-periodic systems, see value_raw for the unfiltered counterpart).
 class TotalForce(PhysicalProperty):
     """
     Section containing the total force of a (sub)system.
@@ -179,6 +156,7 @@ class TotalForce(PhysicalProperty):
     Contains the value and information regarding the total forces on the atoms
     calculated as minus gradient of energy_total.
     """
+
     # ! We need to avoid giving the precise method of calculation without also providing context, this is not necessarily true in general!
 
     value = Quantity(
@@ -189,8 +167,10 @@ class TotalForce(PhysicalProperty):
         """,
     )
 
-    force_contributions = SubSection(sub_section=ForceContributions.m_def, repeats=False)
-    #? Do we need to separate classical and quantum contributions here?
+    contributions = SubSection(
+        sub_section=ForceContributions.m_def, repeats=False
+    )
+    # ? Do we need to separate classical and quantum contributions here?
 
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
diff --git a/src/nomad_simulations/properties/mechanics.py b/src/nomad_simulations/properties/mechanics.py
index bbe418ba..d9a1078a 100644
--- a/src/nomad_simulations/properties/mechanics.py
+++ b/src/nomad_simulations/properties/mechanics.py
@@ -126,4 +126,4 @@ class Stress(MSection):
         Contains other types of stress.
         """,
         repeats=True,
-    )
\ No newline at end of file
+    )
diff --git a/src/nomad_simulations/properties/molecular.py b/src/nomad_simulations/properties/molecular.py
index 931e0930..3905a0a9 100644
--- a/src/nomad_simulations/properties/molecular.py
+++ b/src/nomad_simulations/properties/molecular.py
@@ -49,12 +49,12 @@
 
 
 class RadiusOfGyration(PhysicalProperty):
-
     value = Quantity(
         type=np.float64,
         unit='m',
     )
 
+
 class Hessian(TrajectoryOutputs):
     """
     Section containing the Hessian matrix, i.e., 2nd derivatives with respect to atomic displacements,
@@ -71,7 +71,12 @@ def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
         self.value_unit = 'joule / m ** 2'
         self.name = 'hessian'
-        self.variables = [['atom_index'], ['atom_index'], ['x', 'y', 'z'], ['x', 'y', 'z']]
+        self.variables = [
+            ['atom_index'],
+            ['atom_index'],
+            ['x', 'y', 'z'],
+            ['x', 'y', 'z'],
+        ]
         self.bins = [np.range(self.n_atoms), np.range(self.n_atoms)]
 
 
diff --git a/src/nomad_simulations/properties/thermodynamics.py b/src/nomad_simulations/properties/thermodynamics.py
index ecd1ec62..4598c4f9 100644
--- a/src/nomad_simulations/properties/thermodynamics.py
+++ b/src/nomad_simulations/properties/thermodynamics.py
@@ -38,6 +38,7 @@
 from nomad.metainfo import Quantity, SubSection, MEnum
 from .physical_property import PhysicalProperty
 
+
 class Enthalpy(PhysicalProperty):
     """
     Section containing the enthalpy (i.e. energy_total + pressure * volume.) of a (sub)system.
@@ -54,6 +55,7 @@ class Enthalpy(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class Entropy(PhysicalProperty):
     """
     Section containing the entropy of a (sub)system.
@@ -70,6 +72,7 @@ class Entropy(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class ChemicalPotential(PhysicalProperty):
     """
     Section containing the chemical potential of a (sub)system.
@@ -86,6 +89,7 @@ class ChemicalPotential(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class Pressure(PhysicalProperty):
     """
     Section containing the pressure of a (sub)system.
@@ -102,6 +106,7 @@ class Pressure(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class Virial(PhysicalProperty):
     """
     Section containing the virial (cross product between positions and forces) of a (sub)system.
@@ -118,6 +123,7 @@ class Virial(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class Temperature(PhysicalProperty):
     """
     Section containing the temperature of a (sub)system.
@@ -134,6 +140,7 @@ class Temperature(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class Volume(PhysicalProperty):
     """
     Section containing the volume of a (sub)system.
@@ -150,6 +157,7 @@ class Volume(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 class Density(PhysicalProperty):
     """
     Section containing the density of a (sub)system.
@@ -166,6 +174,7 @@ class Density(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
+
 # ? Does this go here or in energies?
 # ? Naming specific to Potential Energy?
 class Hessian(PhysicalProperty):
@@ -199,6 +208,7 @@ class HeatCapacityCV(PhysicalProperty):
         """,
     )
 
+
 class HeatCapacityCP(PhysicalProperty):
     """
     Section containing the heat capacity at constant volume for a (sub)system.
@@ -215,7 +225,6 @@ class HeatCapacityCP(PhysicalProperty):
     def normalize(self, archive, logger) -> None:
         super().normalize(archive, logger)
 
-
     # ? Is this ever used?
     # internal_energy = Quantity(
     #     type=np.dtype(np.float64),
@@ -234,4 +243,3 @@ def normalize(self, archive, logger) -> None:
     #     Value of the vibrational free energy per cell unit at constant volume.
     #     """,
     # )
-
diff --git a/src/nomad_simulations/test_direct.py b/src/nomad_simulations/test_direct.py
index 88eec4cf..096ac6d5 100644
--- a/src/nomad_simulations/test_direct.py
+++ b/src/nomad_simulations/test_direct.py
@@ -27,10 +27,14 @@
 # Playing with `PhysicalProperty`
 band_gap = ElectronicBandGap(source='simulation', type='direct', label='DFT')
 n_grid_points = 3
-temperature = Temperature(n_grid_points=n_grid_points, grid_points=np.linspace(0, 100, n_grid_points))
+temperature = Temperature(
+    n_grid_points=n_grid_points, grid_points=np.linspace(0, 100, n_grid_points)
+)
 band_gap.variables.append(temperature)
 n_grid_points = 2
-custom_bins = Variables(n_grid_points=n_grid_points, grid_points=np.linspace(0, 100, n_grid_points))
+custom_bins = Variables(
+    n_grid_points=n_grid_points, grid_points=np.linspace(0, 100, n_grid_points)
+)
 band_gap.variables.append(custom_bins)
 # band_gap.value_unit = 'joule'
 # band_gap.shape = [3]