Ligand Field Theory

Question 1

Which orbitals are anti-bonding in a T_d symmetric crystal field?

Answer 1

e

Question 2

Which represents an orbital set that would have e symmetry in a T_d crystal field?

Answer 2

D

Question 3

Tetrahedral transition metal complexes are always_____spin.

High or Low spin

Answer 3

High Spin

Question 4

In an O_h crystal field, the eg orbitals are destabilized.

What is the value of A?

Answer 4

6

Question 5

6 coordinate complexes are generally stable as _____ electron species.

Answer 5

18

Question 6

Square planar complexes are generally stable as _____ electron species.

Answer 6

16

Question 7

In an O_h crystal field, the t_2g orbitals are stabilized.

What is the value of B?

Answer 7

-4

Question 8

What are the irredicuable representions of the ligand’s SALCs of atomic orbitals around a O_h metal complex

Answer 8

a_1g + t_1u + e_g

Question 9

Mixing ligand π charater (π-donor) into the t_2g set of orbitals in an O_h ligand field results in the t_2g set becoming more _________.

Bonding or Antibonding

Answer 9

Antibonding

(Ligand π orbitals are lower in energy than the t_2g set and therefore any mixing results in t_2g inherting antibonding character)

Question 10

Addison Tau Parameters

C_4v

Answer 10

τ=0

α =β =180^o

Question 11

Addison Tau Parameters

D_3h

Answer 11

τ=1

α = 120^o

β = 180^o

Question 12

T_d=AΔ_o

What is the value of A?

Answer 12

4/9

(There are only 4 ligands in a tetrhedral complex. Therefore, the ligand field is roughly 2/3 of the octahedral field)

Question 13

What is the splitting energy of the d-orbitals in an octehedral crystal field?

Answer 13

10D_q or Δ_o

Question 14

What is Δ_o in terms of D_q?

Answer 14

10D_q

Question 15

What is the symmetry of the orbital set below in a O_h ligand field?

Answer 15

e_g

Question 16

What is the symmetry of the orbital set below in a O_h ligand field?

Answer 16

t_2g

Question 17

As the principal quantum number increases, ∆_{o_______.}

Increases or Decreases

Answer 17

Increases

Question 18

As the oxidation state increases,∆_{o_______.}

Increases or Decreases

Answer 18

Increases

Question 19

π-Acceptors_____∆_oh

Increases or Decrease

Answer 19

Increase

Question 20

π-Donors_____∆_oh

Increase or Decrease

Answer 20

Decrease

Question 21

CO, H^-, PPh₃​

Strong or Weak field ligands?

{Rank them}

Answer 21

Strong Field Ligands

PPh₃<h>-<co></co></h>

Question 22

Total Spin

Answer 22

S_tot= (# unpaired e^-)/2

Question 23

2*(S_tot)+1

Answer 23

Spin Multiplicity

Question 24

Quintet

Answer 24

S_tot=2

Question 25

## Footnote **Triplet**

Answer 25

## Footnote **S_tot=1**

Question 26

## Footnote **Doublet**

Answer 26

## Footnote **S_tot=1/2**

Question 27

**Singlet​**

Answer 27

## Footnote **S_tot=0**

Question 28

**I^- ,H₂O ,Cl^-** ***Strong or Weak field ligands?*** ***{Rank Each}***

Answer 28

**Weak Field Ligands** **I^--2O**

Question 29

**I^- ,H₂O ,Cl^-** ***Strong or Weak field ligands?*** ***{Rank Each}***

Answer 29

**Weak Field Ligands** **I^--2O**

Question 30

**Which represents an orbital set that would have t₂ symmetry in a T_d crystal field?**

Answer 30

**C**

Question 31

**Which represents an orbital set that would have t_2g symmetry in a O_h crystal field?**

Answer 31

**B**

Question 32

**Which represents an orbital set that would have e_g symmetry in a O_h crystal field?**

Answer 32

**A**

Question 33

**Which orbitals are antibonding in a T_d symmetric crystal field?**

Answer 33

**t₂**