Magnetic order in the S=1/2 two-dimensional molecular antiferromagnet, copper pyrazine perchlorate Cu(Pz)2(ClO4)2
Abstract
We present an investigation of magnetic ordering in the two-dimensional S=1/2 quantum magnet Cu(Pz)2(ClO4)2 using specific heat and zero field muon-spin relaxation (μ+SR). The magnetic contribution to the specific heat is consistent with an exchange strength of 17.7(3) K. We find unambiguous evidence for a transition to a state of three-dimensional long range order below a critical temperature TN=4.21(1) K using μ+SR even though there is no feature in the specific heat at that temperature. The absence of a specific heat anomaly at TN is consistent with recent theoretical predictions. The ratio of TN/J=0.24 corresponds to a ratio of intralayer to interlayer exchange constants of |J'/J|=6.8x10-4, indicative of excellent two-dimensional isolation. The scaled magnetic specific heat of [Cu(Pz)2(HF2)]BF4, a compound with an analogous structure, is essentially identical to that of Cu(Pz)2(ClO4)2 although both differ slightly from the predicted value for an ideal 2D S=1/2 Heisenberg antiferromagnet.
Turn this paper into a full lesson
ArcXiv compiles a staged curriculum from this paper: 8-12 lessons across beginner → advanced, synthesised section guides, visuals, flashcards, a quiz, exercises, and on-demand deep dives per section. Grounded in the abstract, never invented.