diff --git a/pmd_beamphysics/__init__.py b/pmd_beamphysics/__init__.py
index 2de4f3a..3765851 100644
--- a/pmd_beamphysics/__init__.py
+++ b/pmd_beamphysics/__init__.py
@@ -1,3 +1,3 @@
-from .particles import ParticleGroup
+from .particles import ParticleGroup, single_particle
 from .readers import particle_paths
 from .writers import pmd_init
\ No newline at end of file