We propose to characterise the magnetic ground state structure and the paramagnetic diffuse scattering in a newly synthesised (isotopically enriched) Gd-pyrochlore sample, Gd2Pt2O7. This displays a strong 1st order anomaly in the heat capacity at low temperatures (1.6K) that is consistent with a transition to a "Palmer-Chalker" state, and with a gapped excitation spectrum. Orbital chemistry associated with the Pt ions leads to possible new exchange pathways in this system, which are not present in the stannate or the titanate Gd-pyrochlores. Measurements of the diffuse scattering in the paramagnetic regime will allow us to test this hypothesis, and extract the dominant exchanges. We ask for 5 days on D7 to complete this study.