diff --git a/kernels/neighbor_list.cuh b/kernels/neighbor_list.cuh
index 14d1201..6c02378 100644
--- a/kernels/neighbor_list.cuh
+++ b/kernels/neighbor_list.cuh
@@ -76,12 +76,21 @@ struct CellList {
     return std::make_pair(grid_size, cell_size);
   }
 
-  // Get cell coordinates from position
-  __device__ int3 get_cell_coords(float3 pos) const {
+  __device__ int3 get_cell_coords_from_position(float3 pos) const {
     return make_int3((int)((pos.x - box_min.x) / cell_size.x),
                      (int)((pos.y - box_min.y) / cell_size.y),
                      (int)((pos.z - box_min.z) / cell_size.z));
   }
+
+  __device__ int get_cell_index_from_position(float3 pos) const {
+    return get_cell_index_from_cell_coords(get_cell_coords_from_position(pos));
+  }
+
+  __device__ void assign_particles_to_cells(float3 *positions) {
+    for (int i = 0; i < this->n_particles; i++) {
+      particle_cells[i] = get_cell_index_from_position(positions[i]);
+    }
+  }
 };
 
 #endif