number of metal atom ON = oxidation number of metal and CN = coordination number of complex )
An ion with central metal atom having EAN equal to next inert gas will be more stable .
IUPAC Naming of Complex Compounds
Naming is based on set of rules given by IUPAC .
1 . Name of the compound is written in two parts ( i ) name of cation , and ( ii ) name of anion .
2 . The cation is named first in both positively and negatively charged coordination complexes .
3 . The dissimilar ligands are named in au alphabetical order before the name of central metal atom or ion .
4 . For more then one similar ligands . the prefixes di , tri , tetra , etc are added before its name . If the di , tri , etc already appear in the complex then bis , tris , tetrakis are used .
5 . If the complex part is anion , the name of the central metal ends with suffix ‘ ate ’.
6 . Names of the anionic ligands end in ‘ 0 ’, names of positive ligands end with ‘ ium ’ and names of neutral ligands remains as such . But exception are there as we use aqua for H2O , ammine for NH3 , carbonyl for CO and nitrosyl for NO .
7 . Oxidation state for the metal in cation , anion or neutral coordination compounds is indicated by Roman numeral in parentheses .
8 . The name of the complex part is written as one word .