crystal field splitting (Δ_oct)

difference in energy between the t_2g and e_g sets or t and e sets of orbitals

model that explains the energies of the orbitals in transition metals in terms of electrostatic interactions with the ligands but does not include metal ligand bonding

set of two d orbitals that are oriented on the Cartesian axes for coordination complexes; in octahedral complexes, they are higher in energy than the t_2g orbitals

isomers that differ in the way in which atoms are oriented in space relative to each other, leading to different physical and chemical properties

complex in which the electrons maximize the total electron spin by singly populating all of the orbitals before pairing two electrons into the lower-energy orbitals

complex in which the electrons minimize the total electron spin by pairing in the lower-energy orbitals before populating the higher-energy orbitals

energy required to place two electrons with opposite spins into a single orbital

spectrochemical series

ranking of ligands according to the magnitude of the crystal field splitting they induce

ligand that causes larger crystal field splittings

set of three d orbitals aligned between the Cartesian axes for coordination complexes; in octahedral complexes, they are lowered in energy compared to the e_g orbitals according to CFT

ligand that causes small crystal field splittings

19.3 Spectroscopic and Magnetic Properties of Coordination Compounds: practice

Spectroscopic and Magnetic Properties of Coordination Compounds: practice problems

6 problems from the book, with its answers. Check your working, or have any of them explained to you on the whiteboard.

Exercises 37

Draw the crystal field diagrams for [Fe(NO₂)₆]⁴⁻ and [FeF₆]³⁻. State whether each complex is high spin or low spin, paramagnetic or diamagnetic, and compare Δ $_{oc t}$ to P for each complex.

Exercises 39

Exercises 41

Exercises 43

Exercises 45

Exercises 47

Key terms · 11

crystal field splitting (Δ_oct): difference in energy between the t_2g and e_g sets or t and e sets of orbitals
crystal field theory: model that explains the energies of the orbitals in transition metals in terms of electrostatic interactions with the ligands but does not include metal ligand bonding
e_g orbitals: set of two d orbitals that are oriented on the Cartesian axes for coordination complexes; in octahedral complexes, they are higher in energy than the t_2g orbitals
geometric isomers: isomers that differ in the way in which atoms are oriented in space relative to each other, leading to different physical and chemical properties
high-spin complex: complex in which the electrons maximize the total electron spin by singly populating all of the orbitals before pairing two electrons into the lower-energy orbitals
low-spin complex: complex in which the electrons minimize the total electron spin by pairing in the lower-energy orbitals before populating the higher-energy orbitals
pairing energy (P): energy required to place two electrons with opposite spins into a single orbital
spectrochemical series: ranking of ligands according to the magnitude of the crystal field splitting they induce
strong-field ligand: ligand that causes larger crystal field splittings
t_2g orbitals: set of three d orbitals aligned between the Cartesian axes for coordination complexes; in octahedral complexes, they are lowered in energy compared to the e_g orbitals according to CFT
weak-field ligand: ligand that causes small crystal field splittings

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