The structure of molten ZnCl₂

High energy photon diffraction measurements on molten ZnCl₂ have been carried out in the temperature range 623-853 K. The momentum transfer range covered is 0.15 Å^-1<Q<21.6 Å^-1. The sample is investigated in transmission geometry. The data are in good agreement with neutron diffraction measurements. A discrepancy at smaller Q values is to be noted, however, with earlier studies using conventional Mo-K_α X-rays in reflection geometry. By combining neutron and high energy photon results, the partial distribution functions can be separated to some extent. Almost no change of the first Zn-Cl distance is observed with increasing temperature, whereas the distribution of the first shell Cl-Cl distances increases in width and the first shell Zn-Zn distance decreases.