3rd International Conference on Functional Molecular Materials FUNMAT 2017, Cracovia, Polonia, 8–10 novembre 2017
Reversible Pressure Control on a Zero-Field PseudoOctahedral Cobalt(II) Single-Molecule Magnet Luca Rigamonti,1 Nathalie Bridonneau,1 Giordano Poneti,2 Lorenzo Tesi,3 Lorenzo Sorace,3 Dawid Pinkowicz,4 Andrzej Katrusiak,5 Jesus Jover,6 Eliseo Ruiz,6 Roberta Sessoli,3 Andrea Cornia1 Dipartimento di Scienze Chimiche e Geologiche, Università degli Studi di Modena e Reggio Emilia, via G. Campi 103, 41125 Modena, Italy 2 Instituto de Química, Universidade Federal do Rio de Janeiro, Avenida Athos da Silveira Ramos 149, 21941-909 Rio de Janeiro, Brazil 3 Dipartimento di Chimica ‘Ugo Schiff’, Università degli Studi di Firenze, via della Lastruccia 3-13, 50019 Sesto Fiorentino (FI), Italy 4 Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland 5 Faculty of Chemistry, Adam Mickiewicz University in Poznań, ul. Umultowska 89b, 61-614 Poznań, Poland 6 Departament de Química Inorgànica i Orgànica and Institut de Química Teòrica i Computacional, Universitat de Barcelona, Diagonal 645, 08028 Barcelona, Spain
[email protected] 1
The mononuclear cobalt(II) compound [Co(bpp-COOMe)2](ClO4)2 (1) (bppCOOMe = methyl 2,6-di(pyrazol-1-yl)pyridine-4-carboxylate, see Figure) shows in-field Single-Molecule Magnet (SMM) behavior1,2 as revealed by alternating current (ac) susceptibility measurements. Upon diamagnetic dilution, [Zn0.95Co0.05(bpp-COOMe)2](ClO4)2 (2) shows slow relaxation of magnetization even in zero applied field, thanks to the suppression of dipolar interactions. Single-crystal torque magnetometry and EPR measurements mapped the easy axis nature of this pseudo-octahedral cobalt(II) complex, as also confirmed by theoretical calculations. Underpressure structural and magnetic data of 1, in combination with abinitio calculations, disclosed that the application of an external pressure reversibly slows down the dynamics of the magnetization at low temperature, opening the road towards pressurecontrollable mononuclear SMMs. 1. D. Gatteschi, R. Sessoli, J. Villain, Molecular Nanomagnets, Oxford University Press, Oxford, 2006. 2. a) S. Gómez-Coca, D. Aravena, R. Morales, E. Ruiz, Coord. Chem. Rev. 2015, 289–290, 379–392; b) G. A. Craig, M. Murrie, Chem. Soc. Rev. 2015, 44, 2135–2147; c) J. M. Frost, K. L. M. Harriman, M. Murugesu, Chem. Sci. 2016, 7, 2470–2491.
