prof. dr. E.W. Gorterhis contributions to structural

chemistry in relation to physical properties

Jacob van Dijk (CHG)

Kees Plug (CHG)

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Compliments by W.G.Burgers (1961)

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Evert Willem Gorter

1912 (Leiden) -1972 (Leiden)

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Gorter (left) with J. van Ormondt

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Ferrites

• Early history

– Verwey was first to exploit this research line 1935

– Van Arkel published article with Verwey as early as 1936

– Snoek did write first booklet about ferrites 1947

• Why did ferrites receive so much attention?

– availability cheap raw materials

– electrical isolator

– flexibility of composition & magnetic properties

– novelty

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Spinel Mg Al2O4

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Dilution of M(II)Fe2O4 with Zn

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Predicted Néel anomaly

Li0,5Fe2,5-aCra04

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Néel theory

Super-exchange “model Gorter”

Spin ordering BaFe12O19

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Letter E.W.Gorter

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Gorter: Thesis and Inaugural Address

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Gorter’s approach

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Chemical Composition

Crystal Structure Physical Properties

Gorter with his “blokje”

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Gorter blokje

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Close packed layers A B C

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AB

C

CCP = Cubic Close Packed

FCC = Face Centered Cubic

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AB

C

A

Gorter blokje of NaCl + NiAs

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Gorter blokje of CdCl2 + Cd(OH)2

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Gorter blokje of TiO2 Rutile + Anatase

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Gorter blokje of spinel

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Gorter’s representation of CaFe2O4

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Face shared octahedra

Ca-ion in 9-coordination

Hyde’s representation of CaTi2O4

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Face shared octahedra

Conclusions

– Gorter was eminent scientist/group leader at Philips

directly after the war

• Ferroxcube / Ferroxdure

• Confirmation Neel theory

• Model for super exchange in hexagonal ferrites

– Gorter’s time as professor at Leiden

• Too short to form a real school

• Unique way to represent, understand and inter-relate crystal

structures

• Methodology to predict crystal structures

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We like to thank the following persons who

helped us during the preparation

Family man:

• Eline Schepers (daughter)

• Freek Schepers (grandson)

Professor Leiden:

• Daan IJdo (co-worker)

• Guus Schippers (assistant)

• Jan Reedijk (em prof Leiden)

Philips employee:

• Frans Kools

• George Blasse

• Nol Broese van Groenou

• Coen Rooijmans

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