J. Phys. IV France
Volume 114, April 2004
Page(s) 629 - 631

J. Phys. IV France
114 (2004) 629
DOI: 10.1051/jp4:2004114150

Two hybrid organometallic-inorganic layered magnets from the series [ Z ${^{\rm III}}$Cp *2] [ M ${^{\rm II}}$M ${^{\rm III}}$(ox) 3] studied with $\mu^{+}$SR

T. Lancaster1, 1, S.J. Blundell1, F.L. Pratt2, E. Coronado3 and J.-R. Galán-Mascarós3

1  Clarendon Laboratory, Oxford University Department of Physics, Parks Road, Oxford OX1 3PU, UK
2  ISIS Muon Facility, Rutherford Appleton Laboratory, Chilton, Didcot OX11 0QX, UK
3  Departamento de Química Inorgánica, Universidad de Valencia, Dr. Moliner 50, 46100 Burjasot, Spain

We present zero-field muon spin relaxation (ZF- $\mu^{+}$SR) measurements on two examples of a new series of hybrid organometallic-inorganic layered magnets, namely ferromagnetic [ FeCp *2] [ MnCr(ox) 3] and ferrimagnetic [ CoCp *2] [ FeFe(ox) 3] (where ox = oxalate and Cp * = pentame- thylcyclopentadienyl). Both materials show multi-component muon spin precession signals characteristic of quasistatic magnetic fields at several distinct muon sites. The temperature dependence of the precession frequencies allow critical exponents to be extracted. Possible muon sites are discussed on the basis of dipole field calculations. Key words. Muon-spin relaxation, layered magnets, oxalate complexes.

© EDP Sciences 2004