Which one of the following is an outer orbital complex and exhibits pa...
Which one of the following is an outer orbital complex and exhibits pa...
Outer Orbital Complex and Paramagnetic Behaviour
Outer orbital complex is a type of coordination complex in which the metal ion utilizes its outermost d-orbitals to form coordination bonds with the ligands. These complexes have a high-spin configuration and exhibit paramagnetic behaviour due to the presence of unpaired electrons in the outer d-orbitals.
Explanation of options
a) [Cr(NH3)6]3: This is an inner orbital complex since the Cr(III) ion has a d3 electronic configuration, which leads to the formation of low-spin complexes. Also, all the electrons are paired, so it exhibits diamagnetic behaviour.
b) [Co(NH3)6]3: This is also an inner orbital complex since the Co(III) ion has a d6 electronic configuration, which leads to the formation of low-spin complexes. Also, all the electrons are paired, so it exhibits diamagnetic behaviour.
c) [Ni(NH3)6]2: This complex has a Ni(II) ion with a d8 electronic configuration. Since it is an outer orbital complex, it has unpaired electrons in the outer d-orbitals and exhibits paramagnetic behaviour.
d) [Zn(NH3)6]2: This is not a coordination complex since the Zn(II) ion does not have any d-electrons. Therefore, it does not exhibit any paramagnetic or diamagnetic behaviour.
Conclusion
The correct answer is option C, [Ni(NH3)6]2, which is an outer orbital complex and exhibits paramagnetic behaviour due to the presence of unpaired electrons in the outer d-orbitals.