Crystal Field Theory

$\text{Statement I}$ :  [Ti(H₂O)₆]⁴⁺ is coloured while [Sc(H₂O)₆]³⁺ is colourless.
$\text{Statement II}$ : d - d transition is not possible in [Sc(H₂O)₆]³⁺

The correct order for the wavelengths of absorption in the visible region for the following is: ${\left[\text{Ni}{\left({\text{NO}}_{\text{2}}\right)}_6\right]}^{4-},{\left[\text{Ni}{\left({\text{NH}}_{\text{3}}\right)}_6\right]}^{2+},{\left[\text{Ni}{\left({\text{H}}_{\text{2}}\text{O}\right)}_6\right]}^{2+}$

Which of the following configuration of ions has zero CFSE in both strong and weak ligand fields ?

Which of the following statement is correct ? (CFSE = Crystal Field Splitting Energy)

The correct relation about the value of ${\mathrm{\Delta }}_{\mathrm{o}}$ for the following complexes.

The configuration of central atom is ${\mathrm{t}}_{2\mathrm{g}}^5{\mathrm{e}}_{\mathrm{g}}^0$ for octahedral complex. The correct statement about this compound.

The octahedral complex of a metal ion ${\mathrm{M}}^{3+}$ with four monodentate ligands ${\mathrm{L}}_1, {\mathrm{L}}_2, {\mathrm{L}}_3 \mathrm{and} {\mathrm{L}}_4$ absorb wavelengths in the region of red, green, yellow and blue, respectively. The increasing order of ligand strength of the four ligands is

${\left[\mathrm{S}\mathrm{c}{\left({\mathrm{H}}_2\mathrm{O}\right)}_6\right]}^{3+}$ ion is

In which of the following complexes, magnetic moment will change when all the ligands are replaced by ${\mathrm{CN}}^{-}$ ion to form a cyano complex?

Which of the following compounds is not coloured?

 An octahedral complex $\text{'}\mathrm{X}\text{'}$ with magnetic moment $3.87 \mathrm{BM}$ may have:

(a) ${\mathrm{d}}^3$ configuration with weak field ligand.

(b) ${\mathrm{d}}^3$ configuration with strong field ligand.

(c) ${\mathrm{d}}^6$ configuration with strong field ligand.

(d) ${\mathrm{d}}^7$ configuration with weak field ligand.

Identify the correct set for ${\left[\mathrm{Ni}(\mathrm{CN}{)}_4\right]}^{2-}$:

Crystal field splitting energies for octahedral $\left({\mathrm{\Delta }}_0\right)$ and tetrahedral $\left({\mathrm{\Delta }}_{\mathrm{t}}\right)$ geometries caused by the same ligands are related through the expression

Which one of the following complex has the highest magnitude of Crystal Field Splitting Energy $\left({\mathrm{\Delta }}_0\right)$?

The electronic configuration of $\mathrm{Cr}$ in $\mathrm{Cr}{\left(\mathrm{CO}\right)}_6$ as calculated using crystal field theory is

The order of octahedral crystal field energy for $\text{'}{\mathrm{e}}_{\mathrm{g}}\text{'}$ orbitals are

Which sets of the $\mathrm{d}$$-$orbitals are directly oriented towards the ligands in the octahedral coordination compounds?

A transition metal complex adopts ${\mathrm{t}}_{2 \mathrm{g}}{}^4\mathrm{e}_{\mathrm{g}}^2$ configuration. The nature of ligand surrounding the ion is :-

For next two question please follow the same

When degenerate $\mathrm{d}$-orbitals of an isolated atom/ion come under influence of magnetic field of ligands, the degeneracy is lost. The two set t_2g (d_xy, d_yz,d_xz) and e_g (d_z², d_x²-y²) are either stabilized or destabilized depending upon the nature of magnetic field. It can be expressed diagrammatically as :



Value of $\mathrm{CFSE}$ depends upon nature of ligand and a spectrochemical  series has been made experimentally, for tetrahedral complexes, $\mathrm{\Delta }$ is about $4/9$  times to ${\Delta }_0$ ($\mathrm{CFSE}$ for octahedral complex). This energy lies in visible region and i.e., why electronic transition are responsible for colour. Such transitions are not possible with ${\mathrm{d}}^0$ and ${\mathrm{d}}^{10}$ configuration.

${\mathrm{Cr}}^{3+}$ form four complexes with four different ligands which are [Cr(Cl)₆]^3-, [Cr(H₂O)₆]³⁺, [Cr(NH₃)₆]³⁺ and [Cr(CN)₆]^3-. The order of $\mathrm{CFSE}$ $\left({\Delta }_0\right)$ in these complexes is in the order :