000126494 001__ 126494
000126494 005__ 20240319081007.0
000126494 0247_ $$2doi$$a10.1021/jacs.2c05453
000126494 0248_ $$2sideral$$a130311
000126494 037__ $$aART-2022-130311
000126494 041__ $$aeng
000126494 100__ $$0(orcid)0000-0003-1029-3751$$aRubín, J.$$uUniversidad de Zaragoza
000126494 245__ $$aOrigin of the unusual ground-state spin S = 9 in a Cr10single-molecule magnet
000126494 260__ $$c2022
000126494 5060_ $$aAccess copy available to the general public$$fUnrestricted
000126494 5203_ $$aThe molecular wheel Cr10(OMe)20(O2CCMe3)10], abbreviated {Cr10}, with an unusual intermediate total spin S = 9 and non-negligible cluster anisotropy, D/kB= -0.045(2) K, is a rare case among wheels based on an even number of 3d-metals, which usually present an antiferromagnetic (AF) ground state (S = 0). Herein, we unveil the origin of such a behavior. Angular magnetometry measurements performed on a single crystal confirmed the axial anisotropic behavior of {Cr10}. For powder samples, the temperature dependence of the susceptibility plotted as ¿T(T) showed an overall ferromagnetic (FM) behavior down to 1.8 K, whereas the magnetization curve M(H) did not saturate at the expected 30 µB/fu for 10 FM coupled 3/2 spin Cr3+ions, but to a much lower value, corresponding to S = 9. In addition, the X-ray magnetic circular dichroism (XMCD) measured at high magnetic field (170 kOe) and 7.5 K showed the polarization of the cluster moment up to 23 µB/fu. The magnetic results can be rationalized within a model, including the cluster anisotropy, in which the {Cr10} wheel is formed by two semiwheels, each with four Cr3+spins FM coupled (JFM/kB= 2.0 K), separated by two Cr3+ions AF coupled asymmetrically (J23/kB= J78/kB= -2.0 K; J34/kB= J89/kB= -0.25 K). Inelastic neutron scattering and heat capacity allowed us to confirm this model leading to the S = 9 ground state and first excited S = 8. Single-molecule magnet behavior with an activation energy of U/kB= 4.0(5) K in the absence of applied field was observed through ac susceptibility measurements down to 0.1 K. The intriguing magnetic behavior of {Cr10} arises from the detailed asymmetry in the molecule interactions produced by small-angle distortions in the angles of the Cr-O-Cr alkoxy bridges coupling the Cr3+ions, as demonstrated by ab initio and density functional theory calculations, while the cluster anisotropy can be correlated to the single-ion anisotropies calculated for each Cr3+ion in the wheel.
000126494 536__ $$9info:eu-repo/grantAgreement/ES/DGA/E12-20R$$9info:eu-repo/grantAgreement/ES/AEI/PID2020-115159GB-I00/AEI/10.13039/501100011033$$9info:eu-repo/grantAgreement/ES/MINECO/MAT2017-83468-R
000126494 540__ $$9info:eu-repo/semantics/openAccess$$aAll rights reserved$$uhttp://www.europeana.eu/rights/rr-f/
000126494 592__ $$a5.945$$b2022
000126494 590__ $$a15.0$$b2022
000126494 593__ $$aBiochemistry$$c2022$$dQ1
000126494 591__ $$aCHEMISTRY, MULTIDISCIPLINARY$$b17 / 178 = 0.096$$c2022$$dQ1$$eT1
000126494 593__ $$aColloid and Surface Chemistry$$c2022$$dQ1
000126494 593__ $$aChemistry (miscellaneous)$$c2022$$dQ1
000126494 593__ $$aCatalysis$$c2022$$dQ1
000126494 594__ $$a25.7$$b2022
000126494 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/acceptedVersion
000126494 700__ $$0(orcid)0000-0002-5999-341X$$aArauzo, A.$$uUniversidad de Zaragoza
000126494 700__ $$aBartolomé, E.
000126494 700__ $$aSedona, F.
000126494 700__ $$aRancan, M.
000126494 700__ $$aArmelao, L.
000126494 700__ $$0(orcid)0000-0002-9208-0807$$aLuzón, J.
000126494 700__ $$aGuidi, T.
000126494 700__ $$aWilhelm, F.
000126494 700__ $$aRogalev, A.
000126494 700__ $$aAmann, A.
000126494 700__ $$aSpagna, S.
000126494 700__ $$0(orcid)0000-0002-6517-1236$$aBartolomé, J.$$uUniversidad de Zaragoza
000126494 700__ $$0(orcid)0000-0002-0047-1772$$aBartolomé, F.
000126494 7102_ $$15001$$2065$$aUniversidad de Zaragoza$$bDpto. Ciencia Tecnol.Mater.Fl.$$cÁrea Cienc.Mater. Ingen.Metal.
000126494 7102_ $$12003$$2395$$aUniversidad de Zaragoza$$bDpto. Física Materia Condensa.$$cÁrea Física Materia Condensada
000126494 773__ $$g144, 27 (2022), 12520-12535$$pJ. Am. Chem. Soc.$$tJournal of the American Chemical Society$$x0002-7863
000126494 8564_ $$s2954848$$uhttps://zaguan.unizar.es/record/126494/files/texto_completo.pdf$$yPostprint
000126494 8564_ $$s1018760$$uhttps://zaguan.unizar.es/record/126494/files/texto_completo.jpg?subformat=icon$$xicon$$yPostprint
000126494 909CO $$ooai:zaguan.unizar.es:126494$$particulos$$pdriver
000126494 951__ $$a2024-03-18-14:43:43
000126494 980__ $$aARTICLE