Structure and basic magnetic properties of the honeycomb lattice compounds Na2Co2TeO6 and Na3Co2SbO6

Abstract

The synthesis, structure, and basic magnetic properties of Na 2 Co 2 TeO 6 and Na 3 Co 2 SbO 6 are reported. The crystal structures were determined by neutron powder diffraction. Na 2 Co 2 TeO 6 has a two-layer hexagonal structure (space group P6 3 22) while Na 3 Co 2 SbO 6 has a single-layer monoclinic structure (space group C2/m). The Co, Te, and Sb ions are in octahedral coordination, and the edge sharing octahedra form planes interleaved by sodium ions. Both compounds have full ordering of the Co 2+ and Te 6+ /Sb 5+ ions in the ab plane such that the Co 2+ ions form a honeycomb array. The stacking of the honeycomb arrays differ in the two compounds. Both Na 2 Co 2 TeO 6 and Na 3 Co 2 SbO 6 display magnetic ordering at low temperatures, with what appears to be a spin-flop transition found in Na 3 Co 2 SbO 6 .

Orbitally induced hierarchy of exchange interactions in the zigzag antiferromagnetic state of honeycomb silver delafossite Ag3Co2SbO6

“…S3). It is worth to mention that the spin-reorientation-type transitions have been reported recently for several related antimonates: for example, Na 3 Co 2 SbO 6 [61], Li 3 Ni 2 SbO 6 [63], Na 3 Ni 2 SbO 6 [76], Li 4 FeSbO 6 [67]. …”

“…Nevertheless, crystal structure of Na 3 Co 2 SbO 6 was refined in the monoclinic space group C2/m [61]. Recently, using high-resolution synchrotron data, we definitely confirmed peak splitting and monoclinic symmetry for Na 3 Co 2 SbO 6 , similar to Li 3 Zn 2 SbO 6 [62] and Li 3 Ni 2 SbO 6 [63].…”

Zigzag antiferromagnetic ground state with anisotropic correlation lengths in the quasi-two-dimensional honeycomb lattice compoundNa2Co2TeO6Bera1, Yusuf2, Kumar3 et al. 2017Phys. Rev. B10614873View full textAdd to dashboardCite

“…Recently, density functional theory (DFT) calculations proposed a long-range zigzag AFM ordering for the compounds Li 3 Ni 2 SbO 6 and Na 3 Ni 2 SbO. An AFM ordering at low temperatures was also reported for the O3 type honeycomb compounds Na 3 M 2 SbO 6 (M = Cu, Ni, and Co) [16,31,32], A 3 Ni 2 BiO 6 with A = Na and Li [25,33] and Li 3 Ni 2 SbO 6 [24], as well as for the P2 type compounds Na 2 M 2 TeO 6 (M = Co and Ni) [31,32,34], however, their real quantum ground states remain unknown and await for an experimental investigation. The influence of the intermediate soft Na/Li layers on the magnetic correlations remains as well unexplored in these systems.…”

Zigzag antiferromagnetic quantum ground state in monoclinic honeycomb lattice antimonatesA3Ni2SbO6(A=<

“…No long-range magnetic order was found for honeycomb Na 3 LiFeSbO 6 and Na 4 FeSbO 6 and Li 4 MnSbO 6 probably due to disorder and frustration effects [34,36]. At the same time, honeycomb-ordered O3-derived phases Na 3 M 2 SbO 6 (M=Cu, Ni, Co) [17,19,31], Li 3 Ni 2 SbO 6 [20], Li 3 Ni 2 BiO 6 [21], Na 3 Ni 2 BiO 6 [33], as well as P2-derived Na 2 M 2 TeO 6 (M=Co, Ni) [18,19], were found to order antiferromagnetically at low temperatures but their real quantum ground state remains unknown and requires joint experimental and theoretical efforts to be determined. The influence of the interlayer coupling and of the anisotropy on the ground state in such systems is largely unexplored at present.…”