 In addition to compounds where xenon forms a chemical bond , xenon can form clathrates — substances where xenon atoms or pairs are trapped by the crystalline lattice of another compound . One example is xenon hydrate ( Xe • 5 @.@ 75 H2O ) , where xenon atoms occupy vacancies in a lattice of water molecules . This clathrate has a melting point of 24 ° C. The deuterated version of this hydrate has also been produced . Another example is Xe hydride ( Xe ( H2 ) 8 ) , in which xenon pairs ( dimers ) are trapped inside solid hydrogen . Such clathrate hydrates can occur naturally under conditions of high pressure , such as in Lake Vostok underneath the Antarctic ice sheet . Clathrate formation can be used to fractionally distill xenon , argon and krypton . 
