Effect of Chelate Ring Size in Iron(II) Isothiocyanato Complexes with Tetradentate Tripyridyl-alkylamine Ligands on Spin Crossover Properties

Michael Leibold, Sandra Kisslinger, Frank W. Heinemann, Frank Hampel, Yuko Ichiyanagi, Michael Klein, Patrick Homenya, Franz Renz, Hans Toftlund, Georg Brehm, Siegfried Schneider, Markus Reiher, Siegfried Schindler

  • 1 Citations

Abstract

Iron(II) complexes of the type [Fe(L)(NCS)2] with tetradentate ligands L are well known to show spin crossover properties. However, this behavior is quite sensitive in regard to small changes of the ligand system. Starting from the thoroughly investigated complex [Fe(tmpa)(NCS)2] [tmpa = tris(2-pyridylmethyl)amine, also abbreviated as tpa in the literature] we modified the ligand by increasing systematically the chelate ring sizes from 5 to 6 thus obtaining complexes [Fe(pmea)(NCS)2], [Fe(pmap)(NCS)2], and [Fe(tepa)(NCS)2] [pmea = N,N-bis[(2-pyridyl)methyl]-2-(2-pyridyl)ethylamine, pmap = N,N-bis[2-(2-pyridyl)ethyl]-(2-pyridyl)methylamine, and tepa = tris[2-(2-pyridyl)ethyl]amine]. All complexes were structurally characterized and spin crossover properties were investigated using Möβbauer spectroscopy, magnetic measurements, and IR/Raman analyses. The results demonstrated that only the iron complexes with tmpa and pmea showed spin crossover properties, whereas the complexes with the ligands pmap and tepa only formed high spin complexes. Furthermore, DFT calculations supported these findings demonstrating again the strong influence of ligand environment. Herein the effect of increasing the chelate ring sizes in iron(II) isothiocyanato complexes with tetradentate tripyridyl-alkylamine ligands is clearly demonstrated.

Original languageEnglish
Pages (from-to)85-94
Number of pages10
JournalZeitschrift fur Anorganische und Allgemeine Chemie
Volume642
Issue number1
DOIs
StatePublished - 2016 Jan 1

Fingerprint

Ligands
Iron
Amines
Magnetic variables measurement
Discrete Fourier transforms
Spectroscopy

Keywords

  • Iron
  • LIESST effect
  • Möβbauer
  • Spin crossover
  • Tetradentate pyridyl ligands

ASJC Scopus subject areas

  • Inorganic Chemistry

Cite this

Effect of Chelate Ring Size in Iron(II) Isothiocyanato Complexes with Tetradentate Tripyridyl-alkylamine Ligands on Spin Crossover Properties. / Leibold, Michael; Kisslinger, Sandra; Heinemann, Frank W.; Hampel, Frank; Ichiyanagi, Yuko; Klein, Michael; Homenya, Patrick; Renz, Franz; Toftlund, Hans; Brehm, Georg; Schneider, Siegfried; Reiher, Markus; Schindler, Siegfried.

In: Zeitschrift fur Anorganische und Allgemeine Chemie, Vol. 642, No. 1, 01.01.2016, p. 85-94.

Research output: Contribution to journalArticle

Leibold, M, Kisslinger, S, Heinemann, FW, Hampel, F, Ichiyanagi, Y, Klein, M, Homenya, P, Renz, F, Toftlund, H, Brehm, G, Schneider, S, Reiher, M & Schindler, S 2016, 'Effect of Chelate Ring Size in Iron(II) Isothiocyanato Complexes with Tetradentate Tripyridyl-alkylamine Ligands on Spin Crossover Properties' Zeitschrift fur Anorganische und Allgemeine Chemie, vol 642, no. 1, pp. 85-94. DOI: 10.1002/zaac.201500684

Leibold, Michael; Kisslinger, Sandra; Heinemann, Frank W.; Hampel, Frank; Ichiyanagi, Yuko; Klein, Michael; Homenya, Patrick; Renz, Franz; Toftlund, Hans; Brehm, Georg; Schneider, Siegfried; Reiher, Markus; Schindler, Siegfried / Effect of Chelate Ring Size in Iron(II) Isothiocyanato Complexes with Tetradentate Tripyridyl-alkylamine Ligands on Spin Crossover Properties.

In: Zeitschrift fur Anorganische und Allgemeine Chemie, Vol. 642, No. 1, 01.01.2016, p. 85-94.

Research output: Contribution to journalArticle

@article{bf2514a44cb04252b5d6301343f3a842,
title = "Effect of Chelate Ring Size in Iron(II) Isothiocyanato Complexes with Tetradentate Tripyridyl-alkylamine Ligands on Spin Crossover Properties",
keywords = "Iron, LIESST effect, Möβbauer, Spin crossover, Tetradentate pyridyl ligands",
author = "Michael Leibold and Sandra Kisslinger and Heinemann, {Frank W.} and Frank Hampel and Yuko Ichiyanagi and Michael Klein and Patrick Homenya and Franz Renz and Hans Toftlund and Georg Brehm and Siegfried Schneider and Markus Reiher and Siegfried Schindler",
year = "2016",
month = "1",
doi = "10.1002/zaac.201500684",
volume = "642",
pages = "85--94",
journal = "Zeitschrift fur Anorganische und Allgemeine Chemie",
issn = "0044-2313",
publisher = "Wiley-VCH Verlag",
number = "1",

}

TY - JOUR

T1 - Effect of Chelate Ring Size in Iron(II) Isothiocyanato Complexes with Tetradentate Tripyridyl-alkylamine Ligands on Spin Crossover Properties

AU - Leibold,Michael

AU - Kisslinger,Sandra

AU - Heinemann,Frank W.

AU - Hampel,Frank

AU - Ichiyanagi,Yuko

AU - Klein,Michael

AU - Homenya,Patrick

AU - Renz,Franz

AU - Toftlund,Hans

AU - Brehm,Georg

AU - Schneider,Siegfried

AU - Reiher,Markus

AU - Schindler,Siegfried

PY - 2016/1/1

Y1 - 2016/1/1

N2 - Iron(II) complexes of the type [Fe(L)(NCS)2] with tetradentate ligands L are well known to show spin crossover properties. However, this behavior is quite sensitive in regard to small changes of the ligand system. Starting from the thoroughly investigated complex [Fe(tmpa)(NCS)2] [tmpa = tris(2-pyridylmethyl)amine, also abbreviated as tpa in the literature] we modified the ligand by increasing systematically the chelate ring sizes from 5 to 6 thus obtaining complexes [Fe(pmea)(NCS)2], [Fe(pmap)(NCS)2], and [Fe(tepa)(NCS)2] [pmea = N,N-bis[(2-pyridyl)methyl]-2-(2-pyridyl)ethylamine, pmap = N,N-bis[2-(2-pyridyl)ethyl]-(2-pyridyl)methylamine, and tepa = tris[2-(2-pyridyl)ethyl]amine]. All complexes were structurally characterized and spin crossover properties were investigated using Möβbauer spectroscopy, magnetic measurements, and IR/Raman analyses. The results demonstrated that only the iron complexes with tmpa and pmea showed spin crossover properties, whereas the complexes with the ligands pmap and tepa only formed high spin complexes. Furthermore, DFT calculations supported these findings demonstrating again the strong influence of ligand environment. Herein the effect of increasing the chelate ring sizes in iron(II) isothiocyanato complexes with tetradentate tripyridyl-alkylamine ligands is clearly demonstrated.

AB - Iron(II) complexes of the type [Fe(L)(NCS)2] with tetradentate ligands L are well known to show spin crossover properties. However, this behavior is quite sensitive in regard to small changes of the ligand system. Starting from the thoroughly investigated complex [Fe(tmpa)(NCS)2] [tmpa = tris(2-pyridylmethyl)amine, also abbreviated as tpa in the literature] we modified the ligand by increasing systematically the chelate ring sizes from 5 to 6 thus obtaining complexes [Fe(pmea)(NCS)2], [Fe(pmap)(NCS)2], and [Fe(tepa)(NCS)2] [pmea = N,N-bis[(2-pyridyl)methyl]-2-(2-pyridyl)ethylamine, pmap = N,N-bis[2-(2-pyridyl)ethyl]-(2-pyridyl)methylamine, and tepa = tris[2-(2-pyridyl)ethyl]amine]. All complexes were structurally characterized and spin crossover properties were investigated using Möβbauer spectroscopy, magnetic measurements, and IR/Raman analyses. The results demonstrated that only the iron complexes with tmpa and pmea showed spin crossover properties, whereas the complexes with the ligands pmap and tepa only formed high spin complexes. Furthermore, DFT calculations supported these findings demonstrating again the strong influence of ligand environment. Herein the effect of increasing the chelate ring sizes in iron(II) isothiocyanato complexes with tetradentate tripyridyl-alkylamine ligands is clearly demonstrated.

KW - Iron

KW - LIESST effect

KW - Möβbauer

KW - Spin crossover

KW - Tetradentate pyridyl ligands

UR - http://www.scopus.com/inward/record.url?scp=84954178331&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84954178331&partnerID=8YFLogxK

U2 - 10.1002/zaac.201500684

DO - 10.1002/zaac.201500684

M3 - Article

VL - 642

SP - 85

EP - 94

JO - Zeitschrift fur Anorganische und Allgemeine Chemie

T2 - Zeitschrift fur Anorganische und Allgemeine Chemie

JF - Zeitschrift fur Anorganische und Allgemeine Chemie

SN - 0044-2313

IS - 1

ER -