2026-10-12T13:01:05Z https://api.figshare.com/v2/oai

oai:figshare.com:article/33808009 2026-09-15T17:00:08Z portal_1197 item_type_3 month_year_09_2026

Data for Extremely well-isolated 2D spin-1/2 antiferromagnetic Heisenberg layers with small exchange coupling in the molecular-based magnet CuPOF D. Opherden (24946558) N. Nizar (24946561) K. (Keith) Richardson (24760012) J. C. Monroe (24946564) M. M. Turnbull (2319052) M. Polson (24946567) S. Vela (24946570) William J. A. Blackmore (11873154) Paul Goddard (564595) J. Singleton (2953443) E. S. Choi (24927379) F. Xiao (14026886) R. C. Williams (24863401) T. Lancaster (2511082) F. L. Pratt (2511070) S. J. Blundell (2511079) Y. Skourski (24750961) M. Uhlarz (24750958) A. N. Ponomaryov (24946573) S. A. Zvyagin (1415560) J. Wosnitza (1415557) M. Baenitz (7170695) I. Heinmaa (24946576) R. Stern (11968181) H. Kühne (24946579) C. P. Landee (2319049) Nuclear magnetic resonance spectroscopy Antiferromagnetism Heisenberg uncertainty principle Lattice theory Anisotropy Migrated from ePrints We report on a comprehensive characterization of the newly synthesized Cu2+-based molecular magnet [Cu(pz)2(2−HOpy)2](PF6)2 (CuPOF), where pz=C4H4N2 and 2−HOpy=C5H4NHO. From a comparison of theoretical modeling to results of bulk magnetometry, specific heat, μ+SR, ESR, and NMR spectroscopy, this material is determined as an excellent realization of the two dimensional square-lattice S=12 antiferromagnetic Heisenberg model with a moderate intraplane nearest-neighbor exchange coupling of J/kB=6.80(5) K, and an extremely small interlayer interaction of about 1 mK. At zero field, the bulk magnetometry reveals a temperature-driven crossover of spin correlations from isotropic to XY type, caused by the presence of a weak intrinsic easy-plane anisotropy. A transition to long-range order, driven by the low-temperature XY anisotropy under the influence of the interlayer coupling, occurs at TN=1.38(2) K, as revealed by μ+SR. In applied magnetic fields, our 1H-NMR data reveal a strong increase of the magnetic anisotropy, manifested by a pronounced enhancement of the transition temperature to commensurate long-range order at TN=2.8 K and 7 T.<br><br>Data record consists of a zip archive containing the raw data in .dat format and the accompanying readme file. Data underpins figures 5, 6, S4 and S10 in the corresponding publication. Further information on specific data files can be found in the accompanying readme file. 2026-09-15T17:00:08Z Dataset Dataset 10.82444/warw.33808009.v1 https://figshare.com/articles/dataset/Data_for_Extremely_well-isolated_2D_spin-1_2_antiferromagnetic_Heisenberg_layers_with_small_exchange_coupling_in_the_molecular-based_magnet_CuPOF/33808009 CC BY 4.0