Display of spectra of Transition Metal Aquo ions and simple salts
Aquo Ions.
Ti(III) ~0.02M
Cr(III) ~0.02M
Mn(II) ~1M
Fe(II) ~0.1M
Co(II) ~0.02M
Ni(II) ~0.02M
Cu(II) ~0.02M
 other species
This list will be extended as time allows....
V(IV) as VO2+
[Cr2O7]2-
K3[Cr(ox)3]
Cr(acac)3
K[MnO4]

<-predicted colour of the solution
Expected Values
The expected values should be compared to the following rough guide.
For M2+ complexes, expect Δoct = 7500 - 12500 cm-1 or ν = 800 - 1350 nm.
For M3+ complexes, expect Δoct = 14000 - 25000 cm-1 or ν = 400 - 720 nm.

Δtet ~ 4/9 Δoct.

For first-row transition metal free ions, the size of the B Racah parameter is around 1000 cm-1. For complexes, depending on the position of the ligands in the nephelauxetic series, B' can be reduced to as low as 40%.
The molar absorption coefficients (extinction coefficients) for octahedral complexes are expected to be around 50-100 times smaller than for tetrahedral complexes. For a typical spin-allowed but Laporte (orbitally) forbidden transition in an octahedral complex, expect ε < 10 m2mol-1 (or 100 M-1 cm-1).

Copyright © 2019 by Robert John Lancashire, all rights reserved.

Created and maintained by Prof. Robert J. Lancashire,
The Department of Chemistry, University of the West Indies,
Mona Campus, Kingston 7, Jamaica.