Quasi-One-Dimensional Structure and Possible Helical Antiferromagnetism of RbMn₆Bi₅

Abstract

Quasi-one-dimensional materials exhibit not only unique crystal structure but also abundant physical properties such as charge density wave, Luttinger liquid, and superconductivity. Here we report the discovery, structure, and physical properties of a new manganese-based quasi-one-dimensional material RbMn6Bi5, which crystallizes in a monoclinic space group C2/m (No. 12) with lattice parameters a = 23.286(5) Å, b = 4.6215(9) Å, c = 13.631(3) Å, and β = 125.00(3)°. The structure features [Mn6Bi5]−1 double-walled column extending along the [010] direction, together with Bi–Bi homoatomic bonds linking the columns and the countercation Rb+. The temperature-dependent resistivity clearly indicates a significant resistivity anisotropy for RbMn6Bi5, whereas the magnetic susceptibility and specific heat measurements show that RbMn6Bi5 is antiferromagnetic below 82 K. The density functional theory calculations indicate that RbMn6Bi5 is a quasi-one-dimensional metal with possible helical antiferromagnetic configuration. The discovery of RbMn6Bi5 confirms the viability of discovering new quasi-one-dimensional materials in manganese-based compounds.

ANi5Bi5.6+δ (A = K, Rb, and Cs): Quasi-One-Dimensional Metals Featuring [Ni5Bi5.6+δ]− Double-Walled Column with Strong Diamagnetism

“…For the insulating character of Ntype grease, γ correlated with the electron contribution will not be affected at low temperature, and the large values of γ indicate strong electron correlations 29 in ANi 5 Bi 5.6+δ , consistent with that shown by resistivity. The increasing trend of γ with the increasing cationic radius (Figure 4d) is similar to that of A 2 Mo 3 As 3 (where A = K and Cs), 61 whereas quite different from that in AMn 6 Bi 5 (where A = Na, K, Rb, and Cs) 19,41,42 and A 2 Cr 3 As 3 (where A = K, Rb, and Cs). 29−31 Hence, the DOSs around E F can be tuned by changing the alkali metal or the transition metal in Q1D materials.…”

“…Besides, no apparent anomaly is observed in the resistivity for ANi 5 Bi 5.6+δ . The room-temperature resistivity (ρ 300 K in Table S12 in the Supporting Information) is smaller than that of AMn 6 Bi 5 (0.2–0.44 mΩ cm). ,, The residual resistivity ratios ( RRR = ρ false( normal300 K false) ρ false( normal5 K false) ρ) are ∼6.5, indicating that the crystalline quality of ANi 5 Bi 5.6+δ is good. Above 100 K, the resistivity increases almost linearly with temperature (dashed lines in Figure a), showing that the scattering on phonons dominates in the high-temperature range .…”

“…The room-temperature resistivity (ρ 300 K in Table S12 in the Supporting Information) is smaller than that of AMn 6 Bi 5 (0.2−0.44 mΩ cm). 19,41,42 The residual resistivity ratios (RRR = (300 K)…”

“…Among transition-metal-based Q1D compounds, the ones with pseudo-5-fold symmetry in pentagons ( n = 5) are rare and restricted in certain structures probably due to the incompatibility of the pseudo-5-fold symmetry and translational symmetry. − For example, Na 2.8 Cu 5 Sn 5.6 has Cu 5 and Sn 5 pentagons occupying the same plane, forming a [Cu 5 Sn 5.6 ] 2.8– column with partially occupied Sn site located in the center; INi 5 Bi 5.6 with [Ni 5 Bi 5.6 ] columns shows ferromagnetic (FM) order below 17 K and forms a metastable Ni 5 Bi 5.6 phase with paramagnetic (PM) order by removing I . Recently, a new Q1D system AMn 6 Bi 5 (where A = Na, K, Rb, and Cs) having pseudo-5-fold symmetry was reported with [Mn 6 Bi 5 ] − column formed by Mn/Bi pentagons, showing anisotropic resistivity, antiferromagnetic (AFM) order or various magnetic states. ,, Furthermore, the AFM order in AMn 6 Bi 5 (where A = K, Rb, and Cs) could be suppressed with pressure (∼10 GPa), and then the superconductivity with transition temperature above 9 K having large upper critical field (>20 T) emerges. − These findings inspire researchers to explore new Q1D compounds with transition-metal atomic pentagons, which may exhibit unique properties, like superconductivity or various magnetic states.…”

Pressure-Enhanced Photocurrent in One-Dimensional SbSI via Lone-Pair Electron Reconfiguration

“…To simulate the stereochemical expression of LPEs in SbSI under high pressures, we carried out density functional theory (DFT) calculations on the band structure and electron localization function (ELF) [ 38 , 39 ]. The band structure of SbSI has strong dispersions along the S-Y points, while the Γ-Z-U-R-T-X points are relatively flat, which are typical for electronically 1D band structural motifs ( Figure S6 ) [ 44 , 45 ]. As shown in Figure 4 , it is seen that an apparent non-spherical lobe charge distributes from the Sb atoms, which is regarded as the Sb 3+ -5s 2 LPEs [ 46 ].…”