Speaker: Niloofar Zarifi
Location: Physics 175
Time: 3:30, June 4th, 2014
The presentation can be viewed here.
Abstract: Noble gases are elements with close shell configurations and not expected to form chemical bonding easily except with electronegative halogen atoms. Therefore, these halide compounds have attracted great attentions due to the importance for scientific interest. Here, we performed extensive structure searches on XeClx (x=1, 2 and 4) under high pressure using the GA and PSO methodology. Several novel crystal structures were uncovered for the first time at high pressures. Our calculations confirm existence of molecular Cl2 and Xe atoms in crystalline structures for XeCl. This compound remains an insulator up to 60GPa. The high pressure phase transition has been widely studied for XeCl2. Electronic calculations predicted their metallic property up to 80 GPa. For XeCl4 the metallic state exists at lower pressure.