Revealing the spin structure, exchange constants and local anisotropy in nanoparticles with polarised neutron powder diffraction: Mn3O4 as case study
Year: 2026
Type: article
Abstract: The functional magnetic properties of nanostructured materials can be distinctly different from their bulk counterparts. Understanding these properties is crucial for basic material science and for applications using nanostructured magnetic materials. However, determining intrinsic magnetic structures, exchange constants and local magnetic anisotropy in nanoparticles poses considerable challenges. Here, polarised neutron powder diffraction (PNPD) data, analysed in the frame of the Local Susceptibility and Model Hamiltonian approaches, is used to gain information on the contribution of the different magnetic sublattices on the magnetisation process in Mn 3 O 4 nanoparticles in unprecedented detail. The magnetic order is found to be a Yafet-Kittel-type canted structure with inter- and intra-sublattice antiferromagnetic couplings, similar to bulk. PNPD corroborates that the c-axis is the hard-axis and the individual contributions of each magnetic site to the easy-plane magnetic anisotropy are determined. Remarkably, the analysis of the PNPD data provides the foremost determination of the microscopic magnetic parameters in nanoparticles, namely, intra- and inter- sub-lattice exchange constants and the local anisotropy parameter. The obtained values are consistent with bulk Mn 3 O 4 experimental and theoretical results. These results open the path for the use of PNPD to gain unique magnetic information in nanostructured materials, particularly in complex, novel, or poorly understood systems.
Source: Materials Today
Institutions: European Spallation Source, Centre National de la Recherche Scientifique, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Laboratoire Léon Brillouin, CEA Paris-Saclay, Petersburg Nuclear Physics Institute, Institut Català de Nanociència i Nanotecnologia, Universidad Pública de Navarra (UPNA), Institut de Nanociència i Nanotecnologia de la Universitat de Barcelona, Universitat de Barcelona, Institut Laue-Langevin, Instituto de Nanociencia y Materiales de Aragón, Institució Catalana de Recerca i Estudis Avançats
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $6,070
Funders: Ministerio de Ciencia, Innovación y Universidades, Centres de Recerca de Catalunya, Institut Català de Nanociència i Nanotecnologia, European Commission, Russian Foundation for Basic Research, Generalitat de Catalunya, Departament d’Agricultura, Ramaderia, Pesca i Alimentació, Generalitat de Catalunya, HORIZON EUROPE Framework Programme, Agència de Gestió d'Ajuts Universitaris i de Recerca, Agencia Estatal de Investigación, European Social Fund
Awards: G1119546765, G1175115578, G2064873908, G210041235, G2262748287, G2601397997, G2642906521, G3005324705, G300979063, G3041315068, G34346518, G3480869486, G3546882995, G354764522, G3681454997, G4042783231, G425668148, G4442677895, G4526231891, G5080475149, G5195188938, G5251903276, G546199279, G586857820, G6218905885, G6605876378, G6656126374, G6762955466, G69051668, G7084143925, European network for developing new horizons for RIs, G8637226926, G8888022036
OpenAlex ID: W7168969988