Existence of an antiferromagnetic metallic phase (AFM) in the NiS2−xSex system with pyrite structure

Solid-state selenium-77 NMR

“…However, NiS 2Àx-Se x possesses different electronic properties as a function of x. For x < 0.5 it is a semiconductor, between 0.5 < x < 1.0 the compound is an antiferromagnetic metal at low temperatures, and at x > 1.0 the magnetic ordering is suppressed and the sample remains paramagnetic [273]. Antiferromagnetic ordering in NiS 2Àx Se x (0.5 < x < 1.0) was first reported by Krill and coworkers [274], and recent solidstate 77 Se NMR measurements on x = 0.76 and 0.96 compounds have been contrasted with those from x = 1.25 and 2.00 samples [275].…”

Electrical properties ofNiS2−xSexsingle crystals: From Mott insulator to par

“…We now attempt to correlate the resistivity measurements with phase diagrams cited in the literature; [4][5][6][7]9,13,17,20 these are based on heat capacity, x-ray and neutron scattering, magnetic susceptibility, 77 Se NMR, and 61 Ni Mössbauer data. These phase diagrams are in qualitative agreement with one another, but differ in the exact placement of the phase boundaries on the T vs x plane.…”

Magnetic Phase Diagram and Metal-Insulator Transition of NiS2-xSex

“…An antiferromagnetic (AF) long-range order has been confirmed to exist in both metallic and insulating phases. 6) The AF long-range ordered structure in NiS 2 is complicated showing two types of structure (q M1 = (001) and q M2 = ( 1 2 1 2 1 2 ) on fcc lattice). [7][8][9][10] Although several studies on magnetic phase diagram of NiS 2−x Se x were carried out, 6,[11][12][13][14] there still exist non-trivial discrepancies in the Néel temperature (T N ) and M-I transition temperature (T MI ).…”