We present a single-crystal neutron diffraction study of the magnetic short-range correlations in Tb5Ge4 which orders antiferromagnetically below the Neel temperature TN≈92 K. Strong diffuse scattering arising from magnetic short-range correlations was observed in wide temperature ranges both below and above TN. The antiferromagnetic ordering in Tb5Ge4 is described to consist of strongly coupled ferromagnetic block layers in the ac plane that stack along the b axis with weak antiferromagnetic interlayer coupling. Diffuse scattering was observed along both a∗ and b∗ directions indicating three-dimensional short-range correlations. Moreover, the q dependence of the diffuse scattering is Squared Lorentzian in form suggesting a strongly clustered magnetic state that may be related to the proposed Griffiths-like phase in Gd5Ge4.
Available at: http://works.bepress.com/d_l_schlagel/103/