As Per rules , amine when present as a ligand is written as "ammine" with double m's , so a compound having a complex ligand such as ethane-1,2-diamine , will be written with 1 'm' amine or double 'm' ammine?
1 Answer
As per rules, double m is used when the ligand is just $\ce{NH3}$, ammonia:
Cite from IUPAC Nomenclature of Inorganic Chemistry, Recommendations 2005:
IR-7.1.3 Representing ligands in additive names
Additive names are constructed by placing (sometimes modified) ligand names as prefixes to the name of the central atom. For anionic ligands, the anion endings ‘ide’, ‘ate’ and ‘ite’ (see Section IR-5.3.3) are changed to ‘ido’, ‘ato’ and ‘ito’, respectively, when generating these prefixes. Names of neutral and cationic ligands are used unchanged, except in a few special cases, most notably water (prefix ‘aqua’), ammonia (prefix ‘ammine’), carbon monoxide bound through carbon (prefix ‘carbonyl’), and nitrogen monoxide bound through nitrogen (prefix ‘nitrosyl’) (cf. Section IR-9.2.4.1).
E.g. in $\ce{[CoCl(NH3)5]^{2+}}$ pentaamminechloridocobalt(2+).
For amines, the ligand name is unchanged, e.g.
$\ce{[Co(en)3]^{3+}}$ tris(ethane-1,2-diamine)cobalt(3+).