Pressure response of three-dimensional cyanide-bridged bimetallic magnets

J Am Chem Soc. 2008 Apr 2;130(13):4475-84. doi: 10.1021/ja7110509. Epub 2008 Mar 11.

Abstract

Effects of pressure on the structures and magnetic properties of three types of 3-D cyanide-bridged bimetallic coordination polymer magnets, MnIICrIII ferrimagnet [Mn(en)]3[Cr(CN)6]2.4H2O (1; en = ethylenediamine), NiIICrIII ferromagnet [Ni(dipn)]3[Cr(CN)6]2.3H2O (2; dipn = N,N-di(3-aminopropyl)amine), and NiIIFeIII ferromagnet [Ni(dipn)]2[Ni(dipn)(H2O)][Fe(CN)6]2.11H2O (3), were systematically examined under hydrostatic pressure up to 19.8 GPa using a piston-cylinder-type pressure cell and a diamond anvil cell. The ferrimagnet 1 showed the reversible crystalline-to-amorphous-like phase change, and the magnetic phase transition temperature (TC) was reversibly changed from 69 K at 0 GPa to 126 K at 4.7 GPa. At higher pressure, the net magnetization was suppressed with increasing pressure, and the magnetic state at 19.8 GPa was assumed to be paramagnetic. The initial ferrimagnetic phase of 1 was not recovered after releasing the pressure from 19.8 GPa. The magnetic phase of 2 was reversibly converted between ferromagnetic and paramagnetic-like phase in the range 0 </= P </= 4.7 GPa while maintaining its crystallinity. The porous ferromagnet 3 was easily amorphized and irreversibly lost the ferromagnetic phase under low pressure (P </= 1.0 GPa). The flexible cyanide-bridged magnetic frameworks demonstrate well the pressure response as a reflection of differences in the magnetic structure and the framework strength in the GPa range.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chromium / chemistry*
  • Cyanides / chemistry*
  • Ligands
  • Magnetics*
  • Metals, Heavy / chemistry*
  • Models, Molecular
  • Organometallic Compounds / chemistry*
  • Powder Diffraction
  • Pressure
  • Propylamines / chemistry
  • Temperature

Substances

  • Cyanides
  • Ligands
  • Metals, Heavy
  • N,N-di(3-aminopropyl)amine
  • Organometallic Compounds
  • Propylamines
  • Chromium