A study of the structural and magnetic properties of TlCo2−Cu Se2

The magnetic structure of TlCrTe2

“…TlCrTe 2 was reported as being antiferromagnetic (T N = 140 K) with a positive Curie-Weiss temperature (91 K) [9], however without details of the spin orientation. Antiferromagnetic-layered structures can exhibit very unexpected magnetic structures as found for the case of TlCo 2 Se 2 [10]. Magnetic frustration often occurs in close-packed layers if the magnetic moment lies in the plane.…”

On the magnetic structure of TlCo2Se2

“…The magnetic moments were also calculated. The main contribution to the magnetic moments comes from Co atoms and is 0:72 m B =atom: Thallium and selenium moments are very small, 0.00 and 0:01 m B ; respectively.The interpretation of the previous powder neutron diffraction [4] was somewhat ambiguous due to the low intensities of the magnetic peaks, allowing for other possible explanations. Our theoretical calculation and the single-crystal results confirm the suggested noncollinear incommensurate magnetic structure of…”

“…The interpretation of the previous powder neutron diffraction [4] was somewhat ambiguous due to the low intensities of the magnetic peaks, allowing for other possible explanations. Our theoretical calculation and the single-crystal results confirm the suggested noncollinear incommensurate magnetic structure of…”

“…Powder neutron diffraction [4] data indicated an incommensurate helix running along the caxis with a turn angle of B121 : Newmark et al [5] predicted an antiferromagnetic ordering of the Co atoms between adjacent sheets. The model proposed by Berger et al [4] was deduced from weak magnetic contributions in the powder diffraction pattern, therefore a singlecrystal study was suggested. The results of this experimental work [6] are collected in Table 1. In the present study, we have performed LMTO-ASA calculations [7] for TlCo 2 Se 2 : The self-consistent calculations used spd basis functions centered on all atoms and 15 625 k-points in the Brillouin-zone.…”

“…TlCo 2 Se 2 ; where the Co-Co distances are 2:7 ( A within the sheets and 6:8 ( A between the sheets, is an example of such systems. Recently, the magnetic and crystal structure of this compound has been extensively investigated [4,5]. Powder neutron diffraction [4] data indicated an incommensurate helix running along the caxis with a turn angle of B121 : Newmark et al [5] predicted an antiferromagnetic ordering of the Co atoms between adjacent sheets.…”