Weak ferromagnetism with very large canting in a chiral lattice:Fe(pyrimidine)2Cl2

Abstract

The transition metal coordination compound (pyrimidine)2FeCl2 crystallizes in a chiral lattice, space group I4122 (or I4322). Combined magnetization, Mössbauer spectroscopy and powder neutron diffraction studies reveal that it is a canted antiferromagnet below TN = 6.4 K with an unusually large canting of the magnetic moments of 14• from their general antiferromagnetic alignment, one of the largest reported to date. This results in weak ferromagnetism with a ferromagnetic component of 1 µB. The large canting is due to the interplay between the antiferromagnetic exchange interaction and the local single-ion anisotropy in the chiral lattice. The magnetically ordered structure of (pyrimidine)2FeCl2, however, is not chiral. The implications of these findings for the search of molecule based materials exhibiting chiral magnetic ordering is discussed.

Chiral Molecular Magnets: Synthesis, Structure, and Magnetic Behavior of the Series [M(L‐tart)] (M = MnII, FeII, CoII, NiII; L‐tart = (2R,3R)‐(+)‐tartrate)

“…Although several magnets with chiral crystal structures are known, as discussed in the introduction, the magnetic structure is rarely chiral, [47] and little effect, if any, is observed on the magnetic properties. In this case, we have found rather peculiar magnetic phenomena in this series, but still it is an open question as to whether the magnetic structure of these materials is chiral, as their behavior suggests.…”

Magnetism in ordered metallic perovskite compound

“…The 'S' shape nature of M vs. H data taken at T ¼ 2 K (Fig. 6) suggests the possibility of presence of a canted magnetic structure [11,12] in these two compounds. The suggestion of the canted structure also gets credence from the inverse susceptibility behavior that gets reduced as one approaches the respective transition temperature (Fig.…”

Oxalate‐Based 3D Chiral Magnets: The Series [ZII(bpy)3][ClO4][MIIFeIII(ox)3] (ZII = Fe, Ru; MII = Mn, Fe; bpy = 2,2'‐Bipyridine; ox = Oxalate Dianion)

“…This family constitutes a nice example of chiral magnets, a very sought after combination in recent years [22][23][24] because of the interest in the investigation of how chirality affects the magnetic properties: it is easy to understand that the imposed anisotropy in such systems will be a key factor that controls the magnetic behavior, but further, that these systems could also exhibit new physical phenomena, for example, the so-called magnetochiral dichroism. [25] While the dimetallic 2D magnets have been obtained with a variety of trivalent metals, the analogous 3D systems have only been obtained so far for Cr III .…”