Explain the following : (i) Low spin octahedral complexes of nickel are not known. (ii) The π-complexes are known for transition elements only. (iii) CO is a stronger ligand than NTL, for many metals. -Chemistry

Question

Explain the following : (i) Low spin octahedral complexes of nickel are not known. (ii) The π-complexes are known for transition elements only. (iii) CO is a stronger ligand than NTL, for many metals. -Chemistry

asked Feb 2, 2022 by anonymous

1 Answer

Answer :

(i) The electronic configuration of Ni is [Ar] 3d8 4s2 which shows that it can only form two types of complexes i.e. square planar (dsp2) in presence of strong ligand and tetrahedral (sp3) in presence of weak ligand. There are four empty orbitals in Ni while octahedral complexes require six empty orbitals. (ii) Due to presence of empty d-orbitals in transition metals, they can accept electron pairs from ligands containing π electrons and hence can form ic-bonding complexes. Example : ligands like C5H5, C6H6 etc. (iii) Due to greater magnitude of Δ0, CO produces strong fields which cause more splitting of d-orbitals and moreover it is also able to form π bond due to back bonding.

answered Feb 2, 2022 by anonymous

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