Long-range antiferromagnetic order in malonate-based compounds Na2M(H2C3O4)2·2H2O (M = Mn, Fe, Co, Ni). Issue 6 (4th January 2016)

• Record Type: Journal Article
• Authors: Rousse, G.; Radtke, G.; Klein, Y.; Ahouari, H.
• Is Part Of: Dalton transactions. Volume 45:Issue 6(2016)
• Page Start: 2536
• Page End: 2548
• Publication Date: 2016-01-04
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/c5dt04527d
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : Newly synthetized metal malonates of formulae Na2 M(H2 C3 O4 )2 ·2H2 O (M = Mn, Fe, Co, Ni) exhibit distinct long-range antiferromagnetic orders despite their similar structure and chemistry. Abstract : The recently discovered metal-malonate compounds of formulae Na2 M(H2 C3 O4 )2 ·2H2 O with M = Mn, Fe, Co, Ni are investigated for their magnetic properties. While the Cu-based material is a weak ferromagnet, all other members present antiferromagnetic interactions. Neutron powder diffraction experiments reveal the establishment of a long range magnetic order at low temperature in the Pbca Shubnikov magnetic group. The magnetic structures are characterized by antiferromagnetic layers perpendicular to [001]. These layers are stacked antiparallel (M = Fe) or parallel (M = Mn, Ni) in the ( a, c ) plane. Magnetic moments are collinear to b for the former and to c for the latter. The M = Co malonate exhibits a non-collinear magnetic structure intermediate between the two latter, with components along b and c . Density functional theory calculations indicate that the dominant magnetic interaction, J 1, occurs along a malonate group via a carboxylate and links two transition metals within the same layer, while other interactions (inter- or intra-layer) are much weaker, so that these compounds present the dominant characteristics of 2D-antiferromagnets.