NITROSO no COMPLEXES

If NO reacts with iron to form Fe(NO)s, seventeen electrons are available for bond formation. If the compound really existed it probably would dimerize like Co(CO)4, but what really happens is that the compound Fe(NO)4 is formed. It seems reasonable to assume that the fourth NO molecule only contributes one electron, 

Substitution of O by N in N2 leads to NO, which has one electron in excess and thus easily forms a positive ion in CN there is one electron less than in N2, and thus this compound becomes iso-electronic by attracting one electron and forming the negative ion GN . 

As a univalent ion of medium size, CN , in simple compounds like K+CN , behaves as a chlorine ion, especially if the positive ion has a rare-gas or an 18-electron structure, and covalent bonds cannot be formed. If, however, the positive ion is one of the transition elements, covalent bonds are formed by the lone electron-pair of the CN ion. 

By double decomposition of Ag3Mo(CN)8 with KCN, a complex K4Mo(CN)8 is formed that is remarkable in many ways. In the first place, the reaction 

The Fe(CN) - ion, in which one of the electrons of the stable 18-electron configuration is missing, can withdraw this missing 

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