Abstract
The magnetic configuration of a nanostructure can be altered by an external magnetic field, by spin-transfer torque or by its magnetoelastic response. Here, we explore an alternative route, namely the possibility of switching the sign of the exchange coupling between two magnetic centres by means of an electric potential. This general effect, which we name electrostatic spin crossover, occurs in insulating molecules with super-exchange magnetic interaction and inversion symmetry breaking. As an example we present the case of a family of di-cobaltocene-based molecules. The critical fields for switching, calculated from first principles, are of the order of 1 V nm−1 and can be achieved in two-terminal devices. More crucially, such critical fields can be engineered with an appropriate choice of substituents to add to the basic di-cobaltocene unit. This suggests that an easy chemical strategy for achieving the synthesis of suitable molecules is possible.
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References
Meier, F., Zhou, L., Wiebe, J. & Wiesendanger, R. Revealing magnetic interactions from single-atom magnetization curves. Science 320, 82–86 (2008).
Hirjibehedin, C. F. et al. Large magnetic anisotropy of a single atomic spin embedded in a surface molecular network. Science 317, 1199–1203 (2007).
Slonczewski, J. Current-driven excitation of magnetic multilayers. J. Magn. Magn. Mater. 159, L1–L7 (1996).
Gütlich, P. & Goodwin, H. A. in Spin Crossover in Transition Metal Compounds (eds Gütlich, P. & Goodwin, H. A.) (Springer, 2004).
Sanvito, S. Injecting and controlling spins in organic materials. J. Mater. Chem. 17, 4455–4459 (2007).
Bogani, L. & Wernsdorfer, W. Molecular spintronics using single-molecule magnets. Nature Mater. 7, 179–186 (2008).
Mannini, M. et al. Magnetic memory of a single-molecule quantum magnet wired to a gold surface. Nature Mater. 8, 194–197 (2009).
Timco, G. A. et al. Engineering the coupling between molecular spin qubits by coordination chemistry. Nature Nanotech. 4, 173–178 (2009).
Diefenbach, M. & Kim, K. S. Towards molecular magnetic switching with an electric bias. Angew. Chem. Int. Ed. 46, 7784–7787 (2007).
Nguyen, P., Gómez-Elipe, P. & Manners, I. Organometalic polymers with transition metals in the main chain. Chem. Rev. 99, 1515–1548 (1999).
Van Vleck, J. H. Recent developments in the theory of antiferromagnetism. J. Phys. Radium 12, 262–274 (1951).
Liu, R., Ke, S.-H., Baranger, H. U. & Yang, W. Organometallic spintronics: Dicobaltocene switch. Nano Lett. 5, 1959–1962 (2005).
Ammeter, J. H. & Swalen, J. D. Electronic structure and dynamic Jahn–Teller effect of cobaltocene from EPR and optical studies. J. Chem. Phys. 57, 678–698 (1972).
Hedberg, A. K., Hedberg, L. & Hedberg, K. Molecular structure of di-π-cyclopentadienylcobalt, (C5H5)2Co, by gaseous electron diffraction. J. Chem. Phys. 63, 1262–1266 (1975).
Eicher, H. & Köhler, F. W. Determination of the electronic structure, the spin density distribution, and approach to the geometric structure of substituted cobaltocenes from NMR spectroscopy in solution. Chem. Phys. 128, 297–309 (1988).
Pennanen, T. O. & Vaara, J. Density-functional calculations of relativistic spin–orbit effects on nuclear magnetic shielding in paramagnetic molecules. J. Chem. Phys. 123, 174102 (2005).
Parr, R. G. & Yang, W. Density-Functional Theory of Atoms and Molecules (Oxford Univ. Press, 1989).
Koch, W. & Holthausen, M. A Chemist’s Guide to Density Functional Theory (Wiley–VCH, 2001).
Ahlrichs, R. et al. TURBOMOLE (Vers. 5.9) Universität Karlsruhe, Karlsruhe, Germany. See also: <http://www.turbomole.com> (2007).
Lee, C., Yang, W. & Parr, R. G. Development of the Colle–Salvetti correlation-energy formula into a functional of the electron density. Phys. Rev. B 37, 785–789 (1988).
Becke, A. D. Density-functional thermochemistry. III. The role of exact exchange. J. Chem. Phys. 98, 5648–5652 (1993).
de P. R. Moreira, I., Illas, F. & Martin, R. Effect of Fock exchange on the electronic structure and magnetic coupling in NiO. Phys. Rev. B 65, 155102 (2002).
Schottenberger, H., Rieker, C. & Obendorf, D. Electrochemical properties of two new binuclear ethyne-bridged cobalt complexes: bis-[(η5-cyclopentadienyl)cobalt(η4-1,3-cyclopentadienyl-5-exo-yl)]-ethyne (1) and di-cobaltocenylium-ethyne-di-hexafluorophosphate (2). Electrochem. Acta 38, 1527–1533 (1993).
Rocha, A. R. et al. Towards molecular spintronics. Nature Mater. 4, 335–339 (2005).
Rocha, A. R. et al. Spin and molecular electronics in atomically-generated orbital landscapes. Phys. Rev. B. 73, 085414 (2006).
<http://www.smeagol.tcd.ie>.
Rungger, I. & Sanvito, S. Algorithm for the construction of self-energies for electronic transport calculations based on singularity elimination and singular value decomposition. Phys. Rev. B 78, 035407 (2008).
Toher, C. & Sanvito, S. Effects of self-interaction corrections on the transport properties of phenyl-based molecular junctions. Phys. Rev. B 77, 155402 (2008).
Toher, C. & Sanvito, S. Efficient atomic self-interaction correction scheme for nonequilibrium quantum transport. Phys. Rev. Lett. 99, 056801 (2007).
Ginsberg, A. P. Magnetic exchange in transition metal complexes. 12. Calculation of cluster exchange coupling constants with the X-α-scattered wave method. J. Am. Chem. Soc. 102, 111–117 (1980).
Noodleman, L. Valence bond description of antiferromagnetic coupling in transition metal dimers. J. Chem. Phys. 74, 5737–5743 (1981).
Soda, T. et al. Ab initio computations of effective exchange integrals for H–H, H–He–H and Mn2O2 complex: Comparison of broken-symmetry approaches. Chem. Phys. Lett. 319, 223–230 (2000).
Schäfer, A., Huber, C. & Ahlrichs, R. Fully optimized contracted Gaussian basis sets of triple zeta valence quality for atoms Li to Kr. J. Chem. Phys. 100, 5829–5835 (1994).
Acknowledgements
This work was financially supported by the SpiDME European project (6th Framework Program, NEST) and by the ERC-Starting Grant FP7-Project ‘DEDOM’ (No. 207441). S.S. and N.B. acknowledge CRANN for financial support. Computational resources were provided by NNL-SPACI, by the HEA IITAC project managed by the Trinity Centre for High Performance Computing and by ICHEC. The authors would like to thank E. Fabiano for helpful discussions and M. Margarito for technical support.
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The initial idea of the ESCE was developed by the Dublin team leader, S.S. N.B. and M.P. contributed equally to this work. M.P. carried out the DFT calculations for the exchange coupling constants, and N.B. contributed in developing the simple model and carried out the electric field drop calculations. F.D.S., M.P., S.S. and N.B. designed the molecular structures, and T.T. carried out extra DFT calculations for the exchange coupling. The project was supervised by S.S. and G.M.
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Baadji, N., Piacenza, M., Tugsuz, T. et al. Electrostatic spin crossover effect in polar magnetic molecules. Nature Mater 8, 813–817 (2009). https://doi.org/10.1038/nmat2525
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DOI: https://doi.org/10.1038/nmat2525
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