A novel method for generating molecular mixtures at extreme conditions: The case of fluorine and oxygen

We have successfully created a segregated mixture of molecular fluorine and oxygen at high pressure in a diamond anvil cell (DAC) via useful hard x-ray photochemistry. A keyhole-like sample chamber was created in a stainless steel gasket to hold two segregated powders of potassium tetrafluoroborate (KBF₄) and potassium perchlorate (KClO₄) respectively in each hole at a pressure of ∼3.0 GPa. Both holes were individually irradiated with synchrotron hard x-rays to release molecular fluorine and molecular oxygen, respectively. Upon irradiation of the hole containing KBF₄ molecular fluorine appeared (as evidenced via Raman spectroscopy) near the region of irradiation. The second hole containing KClO₄ was then irradiated and reddish-orange O₂ was observed to form. Oxygen was observed to diffuse throughout both holes. There is some evidence that oxygen difluoride (OF₂) was formed in the hole originally containing the KBF₄.