What was most unusual about this compound was that it contained oxygen in the form of positively charged ions, although oxygen usually has a net negative charge. Oxygen normally pulls electrons from other atoms and is thus called an oxidizing agent or oxidant. But Bartlett believed that in this case, the PtF₆ component was a more powerful oxidizing agent than even oxygen and was extracting electrons from oxygen, leaving oxygen with a net positive charge. Even though PtF₆ was first prepared some years earlier by researchers at Argonne National Laboratory, its oxidizing power had not been recognized until Bartlett's research. It was this development that led Bartlett to theorize that if PtF₆ could oxidize oxygen, then it might also be able to achieve the "impossible" task of oxidizing xenon, whose ionization potential (energy required to remove an electron) was very similar to that of oxygen.