Designing well-defined magnetic nanomaterials is crucial for various applications, and it demands a comprehensive understanding of their magnetic properties at the microscopic level. In this study, we investigate the contributions to the total anisotropy of Mn/Co mixed spinel nanoparticles. By employing neutron measurements sensitive to the spatially resolved surface anisotropy with sub-Å space resolution, we reveal an additional contribution to the anisotropy constant arising from shape anisotropy and interparticle interactions. Our findings shed light on the intricate interplay among chemical composition, microstructure, morphology, and surface effects, providing valuable insights for the design of advanced magnetic nanomaterials for AC biomedical applications, such as cancer treatment by magnetic fluid hyperthermia.

Department of Chemical and Geological Sciences University of Cagliari S S 554 Bivio per Sestu 09042 8 Monserrato CA Italy

Department of Inorganic Chemistry Charles University Hlavova 2030 8 128 43 Prague 2 Czech Republic

Department of Physical and Macromolecular Chemistry Charles University Hlavova 2030 8 128 43 Prague 2 Czech Republic

Dipartimento di Chimica and INSTM Universita'di Firenze Via della Lastruccia 3 1 50019 Sesto Fiorentino Italy

Institute of Physics Faculty of Science P J Šafárik University Park Angelinum 9 04001 Košice Slovakia

ISIS Neutron and Muon Facility Science and Technology Facilities Council Rutherford Appleton Laboratory OX11 0QX Didcot U K

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Muscas G.; Yaacoub N.; Peddis D.. Magnetic Disorder in Nanostructured Materials. In Novel Magnetic Nanostructures; Elsevier, 2018; pp 127–163.

Hochepied J. F.; Pileni M. P. Magnetic properties of mixed cobalt–zinc ferrite nanoparticles. J. Appl. Phys. 2000, 87, 2472–2478. 10.1063/1.372205. DOI

Bender P.; Balceris C.; Ludwig F.; Posth O.; Bogart L. K.; Szczerba W.; Castro A.; Nilsson L.; Costo R.; Gavilán H.; González-Alonso D.; de Pedro I.; Barquín L. F.; Johansson C. Distribution functions of magnetic nanoparticles determined by a numerical inversion method. New J. Phys. 2017, 19, 073012 10.1088/1367-2630/aa73b4. DOI

Mørup S.; Brok E.; Frandsen C. Spin Structures in Magnetic Nanoparticles. J. Nanomater. 2013, 2013, 720629 10.1155/2013/720629. DOI

Gerina M.; Angotzi M. S.; Mameli V.; Gajdošová V.; Rainer D. N.; Dopita M.; Steinke N.-J.; Aurélio D.; Vejpravová J.; Zákutná D. Size dependence of the surface spin disorder and surface anisotropy constant in ferrite nanoparticles. Nanoscale Adv. 2023, 5, 4563–4570. 10.1039/D3NA00266G. PubMed DOI PMC

Aurélio D.; Vejpravova J. Understanding Magnetization Dynamics of a Magnetic Nanoparticle with a Disordered Shell Using Micromagnetic Simulations. Nanomaterials 2020, 10, 1149 10.3390/nano10061149. PubMed DOI PMC

Mikšátko J.; Aurélio D.; Kovaříček P.; Michlová M.; Veverka M.; Fridrichová M.; Matulková I.; Žáček M.; Kalbáč M.; Vejpravová J. Thermoreversible magnetic nanochains. Nanoscale 2019, 11, 16773–16780. 10.1039/C9NR03531A. PubMed DOI

Pacakova B.; Kubickova S.; Salas G.; Mantlikova A. R.; Marciello M.; Morales M. P.; Niznansky D.; Vejpravova J. The internal structure of magnetic nanoparticles determines the magnetic response. Nanoscale 2017, 9, 5129–5140. 10.1039/C6NR07262C. PubMed DOI

Oberdick S. D.; Abdelgawad A.; Moya C.; Mesbahi-Vasey S.; Kepaptsoglou D.; Lazarov V. K.; Evans R. F. L.; Meilak D.; Skoropata E.; van Lierop J.; Hunt-Isaak I.; Pan H.; Ijiri Y.; Krycka K. L.; Borchers J. A.; Majetich S. A. Spin canting across core/shell Fe PubMed DOI PMC

García-Acevedo P.; González-Gómez M. A.; Arnosa-Prieto A.; de Castro-Alves L.; Piñeiro Y.; Rivas J. Role of Dipolar Interactions on the Determination of the Effective Magnetic Anisotropy in Iron Oxide Nanoparticles. Adv. Sci. 2023, 10, 2203397 10.1002/advs.202203397. PubMed DOI PMC

Salazar-Alvarez G.; Qin J.; Šepelák V.; Bergmann I.; Vasilakaki M.; Trohidou K. N.; Ardisson J. D.; Macedo W. A. A.; Mikhaylova M.; Muhammed M.; Baró M. D.; Nogués J. Cubic versus Spherical Magnetic Nanoparticles: The Role of Surface Anisotropy. J. Am. Chem. Soc. 2008, 130, 13234–13239. 10.1021/ja0768744. PubMed DOI

Li W.; Liang Z.; Lu Z.; Tao X.; Liu K.; Yao H.; Cui Y. Magnetic Field-Controlled Lithium Polysulfide Semiliquid Battery with Ferrofluidic Properties. Nano Lett. 2015, 15, 7394–7399. 10.1021/acs.nanolett.5b02818. PubMed DOI

Mohsin A.; Hussain M. H.; Mohsin M. Z.; Zaman W. Q.; Aslam M. S.; Shan A.; Dai Y.; Khan I. M.; Niazi S.; Zhuang Y.; Guo M. Recent Advances of Magnetic Nanomaterials for Bioimaging, Drug Delivery, and Cell Therapy. ACS Appl. Nano Mater. 2022, 5, 10118–10136. 10.1021/acsanm.2c02014. DOI

Zhang Q.; Yang X.; Guan J. Applications of Magnetic Nanomaterials in Heterogeneous Catalysis. ACS Appl. Nano Mater. 2019, 2, 4681–4697. 10.1021/acsanm.9b00976. DOI

Pianciola B. N.; Lima E.; Troiani H. E.; Nagamine L. C.; Cohen R.; Zysler R. D. Size and surface effects in the magnetic order of CoFe DOI

Bonanni V.; Basini M.; Peddis D.; Lascialfari A.; Rossi G.; Torelli P. X-ray magnetic circular dichroism discloses surface spins correlation in maghemite hollow nanoparticles. Appl. Phys. Lett. 2018, 112, 022404 10.1063/1.5006153. DOI

Negi D. S.; Sharona H.; Bhat U.; Palchoudhury S.; Gupta A.; Datta R. Surface spin canting in Fe DOI

Pichon B. P.; Gerber O.; Lefevre C.; Florea I.; Fleutot S.; Baaziz W.; Pauly M.; Ohlmann M.; Ulhaq C.; Ersen O.; Pierron-Bohnes V.; Panissod P.; Drillon M.; Begin-Colin S. Microstructural and Magnetic Investigations of Wüstite-Spinel Core-Shell Cubic-Shaped Nanoparticles. Chem. Mater. 2011, 23, 2886–2900. 10.1021/cm2003319. DOI

del Pozo-Bueno D.; Varela M.; Estrader M.; López-Ortega A.; Roca A. G.; Nogués J.; Peiró F.; Estradé S. Direct Evidence of a Graded Magnetic Interface in Bimagnetic Core/Shell Nanoparticles Using Electron Magnetic Circular Dichroism (EMCD). Nano Lett. 2021, 21, 6923–6930. 10.1021/acs.nanolett.1c02089. PubMed DOI

Bender P.; Wetterskog E.; Honecker D.; Fock J.; Frandsen C.; Moerland C.; Bogart L. K.; Posth O.; Szczerba W.; Gavilán H.; Costo R.; Fernández-Díaz M. T.; González-Alonso D.; Fernández Barquín L.; Johansson C. Dipolar-coupled moment correlations in clusters of magnetic nanoparticles. Phys. Rev. B 2018, 98, 224420 10.1103/PhysRevB.98.224420. DOI

Bender P.; Günther A.; Honecker D.; Wiedenmann A.; Disch S.; Tschöpe A.; Michels A.; Birringer R. Excitation of Ni nanorod colloids in oscillating magnetic fields: a new approach for nanosensing investigated by TISANE. Nanoscale 2015, 7, 17122–17130. 10.1039/C5NR04243G. PubMed DOI

Gazeau F.; Dubois E.; Bacri J.-C.; Boué F.; Cebers A.; Perzynski R. Anisotropy of the structure factor of magnetic fluids under a field probed by small-angle neutron scattering. Phys. Rev. E 2002, 65, 031403 10.1103/PhysRevE.65.031403. PubMed DOI

Zákutná D.; Nižňanský D.; Barnsley L. C.; Babcock E.; Salhi Z.; Feoktystov A.; Honecker D.; Disch S. Field Dependence of Magnetic Disorder in Nanoparticles. Phys. Rev. X 2020, 10, 031019 10.1103/PhysRevX.10.031019. DOI

Sanna Angotzi M.; Mameli V.; Zákutná D.; Kubániová D.; Cara C.; Cannas C. Evolution of the Magnetic and Structural Properties with the Chemical Composition in Oleate-Capped Mn DOI

Zákutná D.; Rouzbeh N.; Nižňanský D.; Duchoň J.; Qdemat A.; Kentzinger E.; Honecker D.; Disch S. Magnetic Coupling in Cobalt-Doped Iron Oxide Core–Shell Nanoparticles: Exchange Pinning through Epitaxial Alignment. Chem. Mater. 2023, 35, 2302–2311. 10.1021/acs.chemmater.2c02813. DOI

De Toro J. A.; Vasilakaki M.; Lee S. S.; Andersson M. S.; Normile P. S.; Yaacoub N.; Murray P.; Sánchez E. H.; Muñiz P.; Peddis D.; Mathieu R.; Liu K.; Geshev J.; Trohidou K. N.; Nogués J. Remanence Plots as a Probe of Spin Disorder in Magnetic Nanoparticles. Chem. Mater. 2017, 29, 8258–8268. 10.1021/acs.chemmater.7b02522. DOI

Frandsen C.; Lefmann K.; Lebech B.; Bahl C. R. H.; Brok E.; Ancoña S. N.; Theil Kuhn L.; Keller L.; Kasama T.; Gontard L. C.; Mørup S. Spin reorientation in α-Fe DOI

Laureti S.; Varvaro G.; Testa A. M.; Fiorani D.; Agostinelli E.; Piccaluga G.; Musinu A.; Ardu A.; Peddis D. Magnetic interactions in silica coated nanoporous assemblies of CoFe PubMed DOI

Aslibeiki B.; Kameli P.; Salamati H.; Concas G.; Fernandez M. S.; Talone A.; Muscas G.; Peddis D. Co-doped MnFe PubMed DOI PMC

Shenker H. Magnetic Anisotropy of Cobalt Ferrite (Co DOI

Hoekstra B.; Brabers V. Magnetocrystalline anisotropy and inversion degree of manganese-ferrous-ferrites. Solid State Commun. 1975, 17, 249–253. 10.1016/0038-1098(75)90286-0. DOI