  We report neutron scattering studies of the spin correlations of the
geometrically frustrated pyrochlore Tb2Mo2O7 using single crystal samples. This
material undergoes a spin-freezing transition below Tg~24 K, similar to
Y2Mo2O7, and has little apparent chemical disorder. Diffuse elastic peaks are
observed at low temperatures, indicating short-range ordering of the Tb moments
in an arrangement where the Tb moments are slightly rotated from the preferred
directions of the spin ice structure. In addition, a Q-independent signal is
observed which likely originates from frozen, but completely uncorrelated, Tb
moments. Inelastic measurements show the absence of sharp peaks due to crystal
field excitations. These data show how the physics of the Tb sublattice
responds to the glassy behavior of the Mo sublattice with the associated
effects of lattice disorder.
