Geometric Isomers (cis / trans).
• These isomers
result from different
relative positions
of the ligands inside the coordination sphere of a TM
complex.
It excludes optical isomers.
• Such isomerism cannot occur for complexes of
coordination numbers 2
and 3, nor for tetrahedral complexes with
coord. no. 4 since all coordination
positions are adjacent to one
another.