Tanabe-Sugano Diagrams and Number

of d-d Transitions

Sulaiman Nasser Al shidhani

Outline

Definition of Tanabe-Sugano diagrams How it determines the d-d transitions for

a metal ion? Tanabe-Sugano diagram for HS & LS

complexes in Oh geometry? Summary References

Tanabe-Sugano diagrams are used in coordination chemistry to predict absorptions in the UV, visible and IR electromagnetic spectrum of coordination compounds

The vertical axis is E/B, where B is a Racah parameter.

The horizontal axis is ∆/B.

How TS diagrams determines the d-d transitions for a metal ion

Determine d electron count Use the appropriate Tanabe-Sugano

Diagram Predict the spin-allowed electronic

transitions

Example:determine the d-d transitions for [V(H2O)6]3+

3 4 5 6 7 8 9 10 11 12

series 1 Sc Ti V Cr Mn Fe Co Ni Cu Zn

series 2 Y Zr Nb Mo Tc Ru Rh Pd Ag Cd

series 3 La Hf Ta W Re Os Ir Pt Au Hg

oxidation state

-IV 7 8 9 10 10 10 10 10 10 10

-III 6 7 8 9 10 10 10 10 10 10

-II 5 6 7 8 9 10 10 10 10 10

-I 4 5 6 7 8 9 10 10 10 10

0 3 4 5 6 7 8 9 10 10 10

I 2 3 4 5 6 7 8 9 10 10

II 1 2 3 4 5 6 7 8 9 10

III 0 1 2 3 4 5 6 7 8 9

IV 0 1 2 3 4 5 6 7 8

V 0 1 2 3 4 5 6 7

VI 0 1 2 3 4 5 6

VII 0 1 2 3 4 5

VIII 0 1 2 3 4

Determine d electron count d2

Use the d2 TS diagram

3T13T2(F)

3T13T1 (P)(F)

3T13A2(F)

Spin allowed transition

TS diagrams for HS & LS in Oh

The diagrams for configurations d4-d7 have a vertical “break” in the diagram. This is due to the shift from a high spin complex to a low spin complex.

LSHS

There is no low-spin or high-spin designation for d2, d3, or d8

All of prepared Ni(II) complexes are d8 and have 3 d-d transitions

3A2g3T1g (P)

3A2g3T2g

3A2g3T1g (F)

Summary

Definition of Tanabe-Sugano diagrams How to determine the d-d transition for

metal ion Tanabe-Sugano diagrams for HS & LS

in Oh geometry

References Inorganic chemistry, Shriver and Atkins, fifth edition. Inorganic chemistry, Catherine E. Housecroft, and

Alan G. Sharpe, second edition. Inorganic chemistry, Gary L. Miessler, and Donald

A. Tarr, fourth edition. http://chemwiki.ucdavis.edu/Inorganic_Chemistry/C

rystal_Field_Theory/Tanabe-Sugano_Diagrams

THE ENDTHANK YOU