# isomerism in coordination complexes

Is there any difference between geometrical and cis-trans isomerism in coordination complexes, because in my book it is given that complexes of the form [Ma4bc] does not show cis-trans isomerism but shows geometrical isomerism

Geometrical isomers are compounds where all atoms are connected to the same atoms but their arrangement in space differs. This does include cis-trans isomers but in the context of coordination compounds also fac-mer isomers ($$\ce{[MA3B3]}$$ cases).
The case of $$\ce{[MA4BC]}$$ is tricky. In principle, they show the same two possible arrangements that, if $$\ce{B}=\ce{C}$$ would be termed cis and trans. In lab practice, most chemists would use cis and trans to describe them. In IUPAC theory, that response and terminology may or may not be valid.