Magnetic ground state of the one-dimensional ferromagnetic chain compoundsM(NCS)2(thiourea)2(M=Ni,Co)
| Autor: | Vivien Zapf, Fan Xiao, Robert C. Williams, S. J. Blundell, Jamie L. Manson, T. J. Hicken, Samuel P. M. Curley, Rebecca Scatena, Piero Macchi, Paul Goddard, Jacqueline A. Villa, Melissa L. Rhodehouse, Elizabeth Krenkel, Jim Eckert, Tom Lancaster |
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| Rok vydání: | 2021 |
| Předmět: |
Materials science
Physics and Astronomy (miscellaneous) Order (ring theory) 02 engineering and technology Electronic structure 021001 nanoscience & nanotechnology 01 natural sciences Heat capacity Crystal Crystallography Ferromagnetism 0103 physical sciences Antiferromagnetism General Materials Science Isostructural 010306 general physics 0210 nano-technology Ground state |
| Zdroj: | Physical Review Materials. 5 |
| ISSN: | 2475-9953 |
| DOI: | 10.1103/physrevmaterials.5.034401 |
| Popis: | The magnetic properties of the two isostructural molecule-based magnets---$\mathrm{Ni}{(\mathrm{NCS})}_{2}{(\mathrm{thiourea})}_{2}, S=1 [\mathrm{thiourea}=\mathrm{SC}{({\mathrm{NH}}_{2})}_{2}]$ and $\mathrm{Co}{(\mathrm{NCS})}_{2}{(\mathrm{thiourea})}_{2}, S=3/2$---are characterized using several techniques in order to rationalize their relationship with structural parameters and to ascertain magnetic changes caused by substitution of the spin. Zero-field heat capacity and muon-spin relaxation measurements reveal low-temperature long-range ordering in both compounds, in addition to Ising-like ($Dl0$) single-ion anisotropy (${D}_{\mathrm{Co}}\ensuremath{\sim}\ensuremath{-}100$ K, ${D}_{\mathrm{Ni}}\ensuremath{\sim}\ensuremath{-}10$ K). Crystal and electronic structure, combined with dc-field magnetometry, affirm highly quasi-one-dimensional behavior, with ferromagnetic intrachain exchange interactions ${J}_{\mathrm{Co}}\ensuremath{\approx}+4$ K and ${J}_{\mathrm{Ni}}\ensuremath{\sim}+100$ K and weak antiferromagnetic interchain exchange, on the order of ${J}^{\ensuremath{'}}\phantom{\rule{4pt}{0ex}}\ensuremath{\sim}\ensuremath{-}0.1$ K. Electron charge- and spin-density mapping reveals through-space exchange as a mechanism to explain the large discrepancy in $J$-values despite, from a structural perspective, the highly similar exchange pathways in both materials. Both species can be compared to the similar compounds $M{\mathrm{Cl}}_{2}{(\mathrm{thiourea})}_{4}, M$ = Ni(II) (DTN) and Co(II) (DTC), where DTN is known to harbor two magnetic-field-induced quantum critical points. Direct comparison of DTN and DTC with the compounds studied here shows that substituting the halide ${\mathrm{Cl}}^{\ensuremath{-}}$ ion for the ${\mathrm{NCS}}^{\ensuremath{-}}$ ion results in a dramatic change in both the structural and magnetic properties. |
| Databáze: | OpenAIRE |
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