Issue 4, 2002
From the journal:

Journal of the Chemical Society, Dalton Transactions

Stereochemical effects on the spin-state transition shown by salts of [FeL2]2+ [L = 2,6-di(pyrazol-1-yl)pyridine]

Joanne M. Holland,a   Judith A. McAllister,bc   Colin A. Kilner,a   Mark Thornton-Pett,a   Adam J. Bridgeman*d  and  Malcolm A. Halcrow*a  

* Corresponding authors

a School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, UK
E-mail: M.A.Halcrow@chem.leeds.ac.uk

b Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, UK

c Interdisciplinary Research Centre in Superconductivity, University of Cambridge, Madingley Road, Cambridge, UK

d Department of Chemistry, University of Hull, Kingston-Upon-Hull, UK
E-mail: A.J.Bridgeman@hull.ac.uk

Abstract

The syntheses of [Fe(L1H)2]X2 (L1H = 2,6-di(pyrazol-1-yl)pyridine [L1H]; X− = BF4−, PF6−) are described. Solvent-free [Fe(L1H)2][BF4]2 shows an approximately D2d-symmetric metal centre in the crystal, and undergoes an unusual abrupt spin-state transition centered at 261 K in the solid, or at 248 K in acetone solution. A solvated phase [Fe(L1H)2][BF4]2·2.9CH3NO2·0.25H2O can be grown at 240 K, which undergoes an irreversible spin-state transition between 260 and 265 K. In contrast, solid [Fe(L1H)2][PF6]2 adopts an unusual C2-symmetric coordination geometry, reflecting a ca. 28° twist of one L1H ligand with respect to each other. This salt is high-spin in the range 10–330 K. DFT calculations have rationalised this unusual structure as a Jahn–Teller distortion of the 5E ground state of the six-coordinate Fe(II) ion. This distortion is favoured by the restricted bite-angle of the L1H ligands.

Graphical abstract: Stereochemical effects on the spin-state transition shown by salts of [FeL2]2+ [L = 2,6-di(pyrazol-1-yl)pyridine]

About
Cited by
Related
Download options Please wait...

Supplementary files

Article information

DOI
https://doi.org/10.1039/B108468M
Article type
Paper
Submitted
18 Sep 2001
Accepted
15 Nov 2001
First published
28 Jan 2002

J. Chem. Soc., Dalton Trans., 2002, 548-554

Permissions

Request permissions

Stereochemical effects on the spin-state transition shown by salts of [FeL2]2+ [L = 2,6-di(pyrazol-1-yl)pyridine]

J. M. Holland, J. A. McAllister, C. A. Kilner, M. Thornton-Pett, A. J. Bridgeman and M. A. Halcrow, J. Chem. Soc., Dalton Trans., 2002, 548 DOI: 10.1039/B108468M

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Spotlight

Advertisements