diff --git a/mace/calculators/mace.py b/mace/calculators/mace.py
index 292b114b..3a8b9e1a 100644
--- a/mace/calculators/mace.py
+++ b/mace/calculators/mace.py
@@ -135,7 +135,7 @@ def __init__(
         r_maxs = np.array(r_maxs)
         assert np.all(
             r_maxs == r_maxs[0]
-        ), "committee r_max are not all the same {' '.join(r_maxs)}"
+        ), f"committee r_max are not all the same {' '.join(r_maxs)}"
         self.r_max = float(r_maxs[0])
 
         self.device = torch_tools.init_device(device)
diff --git a/mace/modules/models.py b/mace/modules/models.py
index c0d8ab43..05ce3864 100644
--- a/mace/modules/models.py
+++ b/mace/modules/models.py
@@ -93,7 +93,7 @@ def __init__(
         )
         edge_feats_irreps = o3.Irreps(f"{self.radial_embedding.out_dim}x0e")
         if pair_repulsion:
-            self.pair_repulsion_fn = ZBLBasis(r_max=r_max, p=num_polynomial_cutoff)
+            self.pair_repulsion_fn = ZBLBasis(p=num_polynomial_cutoff)
             self.pair_repulsion = True
 
         sh_irreps = o3.Irreps.spherical_harmonics(max_ell)
diff --git a/mace/modules/radial.py b/mace/modules/radial.py
index 8dba50cb..72f234fa 100644
--- a/mace/modules/radial.py
+++ b/mace/modules/radial.py
@@ -125,16 +125,16 @@ def __init__(self, r_max: float, p=6):
         )
 
     def forward(self, x: torch.Tensor) -> torch.Tensor:
-        return self._calculate_envelope(x, self.r_max, self.p)
+        return self.calculate_envelope(x, self.r_max, self.p)
 
     @staticmethod
-    def _calculate_envelope(x: torch.Tensor, r_max: float, p: int) -> torch.Tensor:
+    def calculate_envelope(x: torch.Tensor, r_max: float, p: int) -> torch.Tensor:
         r_over_r_max = x / r_max
         envelope = (
-                1.0
-                - ((p + 1.0) * (p + 2.0) / 2.0) * torch.pow(r_over_r_max, p)
-                + p * (p + 2.0) * torch.pow(r_over_r_max, p + 1)
-                - (p * (p + 1.0) / 2) * torch.pow(r_over_r_max, p + 2)
+            1.0
+            - ((p + 1.0) * (p + 2.0) / 2.0) * torch.pow(r_over_r_max, p)
+            + p * (p + 2.0) * torch.pow(r_over_r_max, p + 1)
+            - (p * (p + 1.0) / 2) * torch.pow(r_over_r_max, p + 2)
         )
         return envelope * (x < r_max)
 
@@ -147,6 +147,7 @@ class ZBLBasis(torch.nn.Module):
     """Implementation of the Ziegler-Biersack-Littmark (ZBL) potential
     with a polynomial cutoff envelope.
     """
+
     p: torch.Tensor
 
     def __init__(self, p=6, trainable=False):
@@ -203,7 +204,7 @@ def forward(
         )
         v_edges = (14.3996 * Z_u * Z_v) / x * phi
         r_max = self.covalent_radii[Z_u] + self.covalent_radii[Z_v]
-        envelope = PolynomialCutoff._calculate_envelope(x, r_max, self.p)
+        envelope = PolynomialCutoff.calculate_envelope(x, r_max, self.p)
         v_edges = 0.5 * v_edges * envelope
         V_ZBL = scatter_sum(v_edges, receiver, dim=0, dim_size=node_attrs.size(0))
         return V_ZBL.squeeze(-1)
@@ -255,14 +256,21 @@ def forward(
         )
         Z_u = node_atomic_numbers[sender]
         Z_v = node_atomic_numbers[receiver]
-        r_0 : torch.Tensor = 0.5 * (self.covalent_radii[Z_u] + self.covalent_radii[Z_v])
+        r_0: torch.Tensor = 0.5 * (self.covalent_radii[Z_u] + self.covalent_radii[Z_v])
         r_over_r_0 = x / r_0
         return (
-            1 + (self.a * torch.pow(r_over_r_0, self.q) / (1 + torch.pow(r_over_r_0, self.q - self.p)))
+            1
+            + (
+                self.a
+                * torch.pow(r_over_r_0, self.q)
+                / (1 + torch.pow(r_over_r_0, self.q - self.p))
+            )
         ).reciprocal_()
 
     def __repr__(self):
-        return f"{self.__class__.__name__}(a={self.a:.4f}, q={self.q:.4f}, p={self.p:.4f})"
+        return (
+            f"{self.__class__.__name__}(a={self.a:.4f}, q={self.q:.4f}, p={self.p:.4f})"
+        )
 
 
 @simplify_if_compile