Prediction of the Reactivity of Argon with Xenon under High Pressures

[Image: see text] Pressure significantly modifies the microscopic interactions in the condense phase, leading to new patterns of bonding and unconventional chemistry. Using unbiased structure searching techniques combined with first-principles calculations, we demonstrate the reaction of argon with xenon at a pressure as low as 1.1 GPa, producing a novel van der Waals compound XeAr(2). This compound is a wide-gap insulator and crystallizes in a MgCu(2)-type Laves phase structure. The calculations of phonon spectra and formation enthalpy indicate that XeAr(2) would be stable without any phase transition or decomposition at least up to 500 GPa.