Experimental spin density in the high spin ground state of the Fe8pcl cluster

The spin density determined by polarised neutron diffraction in the S = 10 ground state of the Fe8pcl cluster is reported. The iron experimental spin populations agree with calculations using exact diagonalisation of the magnetic exchange Hamiltonian with experimentally determined J values. This confirms that spin density determination provides valuable information on the relative strengths and signs of the intracluster interactions.