Exploring structural, magnetic and orbital orderings in ZnV2O4

We have been investigating the effect of sample dependence on the magnetic ground state of the geometrically frustrated spinel ZnV2O4. We have prepared two powder samples via two different routes; a conventional sintering route and a novel rapid microwave-assisted route. Our previous characterisation on HRPD and POLARIS show that our sintered sample undergoes a structural transition at ~40 K, however, our microwave sample remains cubic down to 2 K. Due to the inherent broadening of our sintered sample, and the challenges associated with measuring the vanadium sub-lattice using neutrons we have been unable to confirm if the I41/amd structure is correct for our sample. The low temperature structure of ZnV2O4 has been previously confirmed on ID22 and so we feel confident that this is the right instrument for our experiment. We wish to perform a comparative study of our samples, looking for subtleties in the structures to explain why one undergoes a transition and the other does not.