update wfn file parsing

ichor_core/ichor/core/files/gaussian/wfn.py

@@ -4,6 +4,7 @@
 from ichor.core.atoms import Atom, Atoms
 from ichor.core.common.float import from_scientific_double
 from ichor.core.common.itertools import chunker
+from ichor.core.common.str import split_by
 from ichor.core.common.units import AtomicDistance
 from ichor.core.files.file import FileContents, ReadFile, WriteFile
 from ichor.core.files.file_data import HasAtoms, HasData
@@ -97,11 +98,17 @@ def _read_file(self):
 
             line = next(f)
             while not line.startswith(r"CENTRE ASSIGNMENTS"):
-                record = line.split()
+                # have to split like this because
+                # if any coordinate is above -10
+                # there is no whitespace between the coordinates
+                # so cannot split directly by whitespace
+                record = split_by(
+                    line, [4, 4, 16, 12, 12, 12, 10], return_remainder=True
+                )
                 atom_type = record[0]
-                x = float(record[-6])
-                y = float(record[-5])
-                z = float(record[-4])
+                x = float(record[3])
+                y = float(record[4])
+                z = float(record[5])
                 # _ = float(record[-1])  # nuclear charge, not used
                 atoms.add(
                     Atom(