Cr-Cr distance and magnetism in the phase diagram of triangular lattice antiferromagnets: A systematic comparative study

In this study, we investigate the influence of Cr-Cr distances on the magnetic properties of triangular lattice antiferromagnets through the lens of the recently synthesized Cr compounds <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:msub><a:mi>LiCrSe</a:mi><a:mn>2</a:mn></a:msub></a:math>, <b:math xmlns:b="http://www.w3.org/1998/Math/MathML"><b:msub><b:mi>LiCrTe</b:mi><b:mn>2</b:mn></b:msub></b:math>, and <c:math xmlns:c="http://www.w3.org/1998/Math/MathML"><c:msub><c:mi>NaCrTe</c:mi><c:mn>2</c:mn></c:msub></c:math>. Our comprehensive analysis integrates existing magnetic structure data and new insights from muon spin rotation measurements, revealing a striking mutual influence between strongly correlated electrons and structural degrees of freedom in systems possessing very different magnetic properties despite having the same crystal symmetry. In particular, we delineate how Cr-Cr distances specifically dictate the magnetic behaviors of the triangular lattice antiferromagnets <d:math xmlns:d="http://www.w3.org/1998/Math/MathML"><d:msub><d:mi>LiCrSe</d:mi><d:mn>2</d:mn></d:msub></d:math>, <e:math xmlns:e="http://www.w3.org/1998/Math/MathML"><e:msub><e:mi>LiCrTe</e:mi><e:mn>2</e:mn></e:msub></e:math>, and <f:math xmlns:f="http://www.w3.org/1998/Math/MathML"><f:msub><f:mi>NaCrTe</f:mi><f:mn>2</f:mn></f:msub></f:math>. By crafting phase diagrams based on these distances, we establish a clear correlation between the structural parameters and the magnetic ground states of these materials together with a wide variety of trivalent Cr triangular lattice layered magnets. Our analysis uncovers a transition range for in-plane and out-of-plane Cr-Cr distances that demarcates distinct magnetic behaviors, highlighting the nuanced role of lattice geometry in the spin-lattice interaction and electron correlation dynamics. Published by the American Physical Society 2024