Mössbauer spectroscopy of magnetic phases in FeCl2 · 2H2O

Abstract

Mossbauer spectroscopy of the three magnetic phases of single crystal FeCI 2 · 2H2 0 in ex ternal magnetic fields at 4.2 K is reported.

Two-Dimensional Coordination Polymers with One-Dimensional Magnetic Chains: Hydrothermal Synthesis, Crystal Structure, and Magnetic and Thermal Properties of [MCl2(4,4‘-bipyridine)] (M = Fe, Co, Ni, Co/Ni)

“…The critical field, determined as the field under which the cusp in χ( T ) measurement disappears, for I , II , III , and IV are 3.5, 2.5, 12, and 7 kG, respectively. The metamagnetic transitions observed in the MCl 2 (4,4‘-bpy) series resemble that found in the similar chain systems MCl 2 ·2H 2 O (M = Fe and Co), − and M(pyridine) 2 Cl 2 (M = Fe, Co, and Ni). − However, the critical fields for the title compounds are much lower than thatin the MCl 2 ·2H 2 O and close to that found in the M(pyridine) 2 Cl 2 systems.…”

“…We have focused on the systems containing magnetically active metal centers, since strong magnetic exchange interactions are expected in these systems through relatively closely placed metal species (∼3.6 Å). Studies on magnetic properties have been reported on a number of compounds that are structurally related to metal dichloride 4,4‘-bpy adducts, including MCl 2 ·2H 2 O (M = Fe and Co), − M(pyridine) 2 Cl 2 (M = Fe, Co, and Ni), − and [(CH 3 ) 3 NH]CoCl 3 ·2H 2 O, all containing polymeric chains of (−MCl 2 −) units. Investigation of the title compounds may reveal some interesting features regarding the magnetic ordering temperature and the type of the ground state ordering for single and mixed metal systems, thus providing further test of the theoretical models used in earlier studies of the MCl 2 chain compounds.…”

Amorphization of S, Cl‐Salts Induced by Martian Dust Activities

“…These data are interpreted within the context of broader work on MB of minerals with similar structures. Only a handful of Mössbauer spectra could be found in the literature for iron dichloride tetrahydrate, and most of the papers do not provide explicit parameters (Ohshita et al, 2002) or focus on LT (Shinohara, 1977) or magnetic field measurements (Johnson, 1966;Kandel et al, 1974;Spiering et al, 1978) that are not comparable to this study. Overall, the analyzed sample contains 88% of the total Fe as Fe 3+ , which was 0% in the starting phase of FeCl 2 •4H 2 O.…”