diff --git a/python/converters/vasp/python/vaspio.py b/python/converters/vasp/python/vaspio.py
index f3d96105..473f7a49 100644
--- a/python/converters/vasp/python/vaspio.py
+++ b/python/converters/vasp/python/vaspio.py
@@ -173,7 +173,11 @@ class Poscar:
 
 # Read atomic positions
         self.q_types = []
+        self.type_of_ion = []
         for it in xrange(self.ntypes):
+# Array mapping ion index to type
+            self.type_of_ion += self.nions[it] * [it]
+
             q_at_it = np.zeros((self.nions[it], 3))
             for iq in xrange(self.nions[it]):
                 sline = readline_remove_comments()
diff --git a/python/converters/vasp/test/_vaspio/POSCAR.complex b/python/converters/vasp/test/_vaspio/POSCAR.complex
new file mode 100644
index 00000000..c7693ced
--- /dev/null
+++ b/python/converters/vasp/test/_vaspio/POSCAR.complex
@@ -0,0 +1,28 @@
+NdNiO3
+1.0
+        5.3871197701         0.0000000000         0.0000000000
+        0.0000000000         5.3826699257         0.0000000000
+        0.0000000000         0.0000000000         7.6093997955
+   Nd   Ni    O
+    4    4   12
+Direct
+     0.995800018         0.035000000         0.250000000
+     0.004199982         0.964999974         0.750000000
+     0.495800018         0.465000004         0.750000000
+     0.504199982         0.535000026         0.250000000
+     0.500000000         0.000000000         0.000000000
+     0.000000000         0.500000000         0.000000000
+     0.500000000         0.000000000         0.500000000
+     0.000000000         0.500000000         0.500000000
+     0.069300003         0.489699990         0.250000000
+     0.930700004         0.510300040         0.750000000
+     0.569299996         0.010300010         0.750000000
+     0.430700004         0.989699960         0.250000000
+     0.716600001         0.287099987         0.039500002
+     0.283399999         0.712900043         0.960500002
+     0.216600001         0.212900013         0.960500002
+     0.783399999         0.787099957         0.039500002
+     0.283399999         0.712900043         0.539499998
+     0.716600001         0.287099987         0.460500002
+     0.783399999         0.787099957         0.460500002
+     0.216600001         0.212900013         0.539499998
diff --git a/python/converters/vasp/test/_vaspio/test_poscar.py b/python/converters/vasp/test/_vaspio/test_poscar.py
index bfe4420c..10f7b395 100644
--- a/python/converters/vasp/test/_vaspio/test_poscar.py
+++ b/python/converters/vasp/test/_vaspio/test_poscar.py
@@ -18,6 +18,7 @@ class TestPoscar(mytest.MyTestCase):
 
     Scenarios:
     - correct POSCAR file
+    - check 'type_of_ion' array for a complex POSCAR file
 
     """
 # Scenario 1
@@ -41,3 +42,12 @@ class TestPoscar(mytest.MyTestCase):
         expected = 'POSCAR.example.out'
         self.assertFileEqual(testout, expected)
 
+# Scenario 2
+    def test_type_of_ion(self):
+        filename = 'POSCAR.complex'
+        poscar = Poscar()
+        poscar.from_file(vasp_dir='./', poscar_filename=filename)
+
+        test_types = 4 * [0] + 4 * [1] + 12 * [2]
+        self.assertListEqual(test_types, poscar.type_of_ion)
+