Long-range magnetic order and interchain interactions in theS=2chain systemMnCl3(bpy)

Abstract

A compound with very weakly interacting chains, MnCl3(bpy), has attracted a great deal of attention as a possible S = 2 Haldane chain. However, long-range magnetic order of the chains prevents the Haldane gap from developing below 11.5 K. Based on a four-sublattice model, a description of the antiferromagnetic resonance (AFMR) spectrum up to frequencies of 1.5 THz and magnetic fields up to 50 T indicates that the interchain coupling is indeed quite small but that the Dzaloshinskii-Moriya interaction produced by broken inversion symmetry is substantial (0.12 meV). In addition, the antiferromagnetic, nearest-neighbor interaction within each chain (3.3 meV) is significantly stronger than previously reported. The excitation spectrum of this S = 2 compound is well-described by a 1/S expansion about the classical limit.

Field-induced quantum magnetism in the verdazyl-based charge-transfer salt[o−MePy−V−(p−Br)2]Iwasaki1, Kida2, Hagiwara3 et al. 2018Phys. Rev. B6000View full textAdd to dashboardCite

“…8. Since a zero-field gap of ∼15 GHz, which corresponds to the energy scale of H SF , is expected from the extrapolation of the resonance modes, the observed resonance fields sug- gest conventional AF resonance modes in an anisotropic two-sublattice model [21,[29][30][31][32][33]. The anisotropic energy derived from the dipole−dipole interactions is confirmed to induce observable magnetic anisotropy even in isotropic radical sysytems [21,29].…”

S=2 Quantum Spin Chain with the Biquadratic Exchange Interaction

“…Then if the ground state is in the intermediate-D phase, the 1/2 magnetization plateau would appear in the magnetization curve. The candidate materials of the quasi-one-dimensional S = 2 antiferromagnet are as follows: MnCl 3 (bpy), [40][41][42] [Mn(hfac) 2 ]•(o-Py-V), 43,44 MnF(salen), 45 and Pb 2 Mn(VO 4 ) 2 (OH). 46 The 1/2 magnetization plateau has not been discovered for those candidate materials, yet.…”

Structure and Magnetism of an Ideal One-Dimensional Chain Antiferromagnet [C2NH8]3[Fe(SO4)3] with a Large Spin of S = 5/2

“…Large- S 1D chains are not extensively investigated because quantum magnetism in these systems decays with increasing S and even a small interchain exchange interaction can enable long-range AFM ordering. For a chain with integer spins, the Haldane gap decreases from 0.41 J of S = 1–0.08 J of S = 2, where J is the strength of the nearest-neighboring exchange. , Experimentally, [Mn-(bipy)­Cl 3 ] was initially considered as the first example of the S = 2 Haldane gap system, but later was identified as a magnetically ordered system . Mn­(III)­F­(salen) is an S = 2 linear-chain compound with a long-range ordering at T N = 23 K, while [Mn­(hfac) 2 ]·( o -Py-V) is an unconventional alternating chain system exhibiting disorder, Ising anisotropy, and 1/4 magnetization plateau …”

“…15,16 Experimentally, [Mn-(bipy)Cl 3 ] was initially considered as the first example of the S = 2 Haldane gap system, 17 but later was identified as a magnetically ordered system. 18 Mn(III)F(salen) is an S = 2 linear-chain compound with a long-range ordering at T N = 23 K, 19 while [Mn(hfac) 2 ]• (o-Py-V) is an unconventional alternating chain system exhibiting disorder, Ising anisotropy, and 1/4 magnetization plateau. 20 More research studies have focused on the chains with halfinteger spins such as the S = 3/2 Heisenberg chain Na 2 Mn 3 O 7 , 21 S = 5/2 alternating chain FeSeO 3 F, 22 linear-chain SrMn(VO 4 )(OH), 23 screw chain SrMn 2 V 2 O 8 , 24 zigzag chain Ba 3 Fe 2 Ge 4 O 14 25 and Bi 2 Fe(SeO 3 )OCl 3 , 26 and triangular chain Bi 3 FeMo 2 O 12 .…”