A recent study by scientists from North Carolina State University, Princeton, and Texas A&M University, published in Nature Communications, brings exciting news about atomic oxygen in water. They found that atomic oxygen can exist in water for hundreds of microseconds and can penetrate several hundred micrometers deep. This discovery challenges what we previously understood about atomic oxygen’s behavior in liquid.
Atomic oxygen is highly reactive and plays a role in various medical and industrial applications. However, measuring its behavior in water has been tough because water quickly deactivates excited oxygen atoms, making it hard to study them.
To tackle this issue, the researchers used a technique called two-photon absorption laser-induced fluorescence (TALIF). This method allows them to excite oxygen atoms by making them absorb two photons at once. As these atoms return to their stable state, they emit light that scientists can measure. By using a femtosecond laser, which delivers extremely short pulses of light, they were able to capture the fluorescence before the surrounding water could deactivate the oxygen.
The findings showed atomic oxygen reaching densities of about 10¹⁶ atoms per cubic centimeter near the water surface. This persistence for such a reactive species is notable. The researchers highlighted that existing models of oxygen’s reactivity in water will need updating based on these results.
Interestingly, there’s a historical backdrop here. In the past, many believed that such reactive atoms could not survive in water long enough to be studied. This new insight forces a reevaluation of traditional assumptions in fields like chemistry and molecular biology.
However, the researchers pointed out some limitations. They assumed that all collisions between excited oxygen atoms and water molecules lead to deactivation. If some collisions don’t result in quenching, their density estimates might be too high. This nuanced finding indicates the ongoing complexity of measuring these fleeting chemical interactions.
Excitingly, this research paves the way for better understanding oxygen chemistry in liquid environments. As noted in Popular Mechanics, this breakthrough opens new doors for future studies that could refine our knowledge in this area.
For more details on this research, check out the original study here.
