The interaction between magnetism and the nuclear lattice is investigated
experimentally, using thermal expansion, magnetostriction, specific heat,
magnetisation and neutron scattering measurements. Both localised moment
systems, as represented by the rare earth compounds Tb2Agln, Pd2Gdln and
Cu2Gdln, as well as transition metal compounds, Ni2MnGa and V20 3 have been
characterised at low temperatures.
Measurements of the lattice properties are important due to the intrinsic
coupling of magnetic degrees of freedom to them. The response of the lattice to
magnetic order, and also to applied magnetic fields have been probed by the
use of the aforementioned techniques. Such techniques allow the direct
determination of the coefficient of linear thermal expansion, over a wide
temperature range and the forced magnetostriclion in applied fields of 0 to 7T.
Indirect determination of the spontaneous magnetostriction and the total
magnetic entropy contribution via measurements of isostructural compounds
further enhance the range of experimental data available. The dynamic
properties are characterised by spin polarised neutron scattering
The experimental results are presented and discussed. Various methods of
coupling lattice and electronic degrees of freedom have been investigated.
It is argued that in order to fully understand and appreciate the low temperature
properties of the materials investigated such a coupling must be taken into
A Doctoral Thesis. Submitted in partial fulfillment of the requirements for the award of Doctor of Philosophy of Loughborough University.