Interplay of nematic and magnetic orders in FeSe under pressure

We offer an explanation for the recently observed pressure-induced magnetic state in the iron-chalcogenide FeSe based on \textit{ab initio} estimates for the pressure evolution of the most important Coulomb interaction parameters. We find that an increase of pressure leads to an overall decrease mostly in the nearest-neighbor Coulomb repulsion, which in turn leads to a reduction of the nematic order and the generation of magnetic stripe order. We treat the concomitant effects of band renormalization and the induced interplay of nematic and magnetic order in a self-consistent way and determine the generic topology of the temperature-pressure phase diagram, and find qualitative agreement with the experimentally determined phase diagram.Comment: 13 pages, 6 fig

Mechanomagnetics in elastic crystals: insights from [Cu(acac)2]

We predict that the magnetic properties of [Cu(acac) ], an elastically flexible crystal, change drastically when the crystal is bent. It is found that unbent [Cu(acac) ] is an almost perfect Tomonaga-Luttinger liquid. Broken-symmetry density-functional calculations reveal that the magnetic exchange interactions along the chains are an order of magnitude larger than the interchain exchange. The geometrically frustrated interchain interactions cannot magnetically order the material at any experimentally accessible temperature. The ordering temperature (T ), calculated from the chain-random-phase approximation, increases by 24 orders of magnitude when the material is bent. We demonstrate that geometric frustration both suppresses T and enhances the sensitivity of T to bending. In [Cu(acac) ], T is extremely sensitive to bending but remains too low for practical applications, even when bent. Partially frustrated materials could achieve the balance of high T and good sensitivity to bending required for practical applications of mechanomagnetic elastic crystals

Erratum: Spin molecular-orbit coupling and magnetic properties of the decorated honeycomb layers of Mo3S7(dmit)3 crystals (vol 8, 101430, 2018)

This article was originally published online on 19 October 2018 with author Amie L. Khosla misspelled. The author name is correct as it appears above. All online versions of the article were corrected on 22 January 2019

Spin molecular-orbit coupling and magnetic properties of the decorated honeycomb layers of Mo3S7(dmit)3 crystals

We explore the magnetic properties of isolated a − b planes of trinuclear organometallic crystals, Mo3S7(dmit)3, in which an interplay of strong electronic correlations and spin molecular-orbital coupling (SMOC) occurs. The magnetic properties can be described by a XXZ+1200, S = 1 Heisenberg model on a honeycomb lattice with single-spin anisotropy, D, which depends strongly on SMOC. Based on ab initio estimates of SMOC in Mo3S7(dmit)3 crystals, we predict that the honeycomb layers of Mo3S7(dmit)3 are Néel ordered. However, in materials with a greater degree of magnetic frustration, Néel order can give way to a large-D phase