Neutron total scattering measurements were performed at the NOMAD beamline at the Spallation Neutron Source (SNS). Samples were loaded into vanadium sample cans and placed into the vanadium furnace to measure the sample from room temperature up to 700 °C. The sample was heated using the vanadium furnace provided at the beamline; the sample was measured upon heating with an exposure time of 5 minutes for each measurement. Once the sample reached 550 °C and 700 °C, the sample was measured for 7.6 hours at each temperature. The measurements at the beamline were calibrated using standard samples such as diamond and vanadium. The measurements were background corrected by subtracting the empty sample container. The raw neutron scattering intensity was converted to the total (static) structure factor S(Q) with corrections using the software ADDIE at the beamline (shown in Figs. S5 † and S6 † ). Q is the scattering vector and is defined as Q = 4π λ sin θ for elastic scattering, where λ is the wavelength of the radiation and 2θ is the diffraction angle. X-ray diffraction measurements were conducted at the PDF beamline (28-ID-1) at the National Synchrotron Light Source II (NSLS-II). The sample was placed in a novel sample holder designed to contain molten salts that includes a sealed quartz capillary with a capped graphite insert to hold the salt. The X-ray measurements were performed with an amorphous siliconbased flat panel detector mounted orthogonal to the beam path that moved between two distances for pair distribution function (PDF) and X-ray diffraction (XRD) measurements. The distance was calibrated by measuring a LaB 6 standard sample. The sample was heated using a hot-air blower at a rate of 5 °C per minute until reaching 510 °C. The sample was measured while heating with an exposure time of 30 seconds for each measurement. Once at 510 °C, the sample was measured with an exposure time of approximately 5 minutes. The raw 2D detector images were corrected using standard procedures such as subtracting the detector dark current and masking regions with artifacts. The corrected images were radially integrated and converted into the scattering intensity as a function of the scattering vector Q. Patterns were also measured of the empty graphite quartz container and ). The X-ray scattering intensities were converted into the total structure factor S(Q) using the software PDFgetX3 that uses an ad hoc data correction method to obtain the coherent X-ray scattering intensities. The sample temperature was calculated by the methods described in Sprouster et al. .