Dalian Coherent Light Source reveals strong isotope effects in photodissociation of water isotopolog eurekalert.org - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from eurekalert.org Daily Mail and Mail on Sunday newspapers.
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IMAGE: Dalian Coherent Light Source revealing three-body photodissociation of water as an important prebiotic-O2 source view more
Credit: DICP
The provenance of oxygen on Earth and other solar planetary bodies is a fundamental issue. It is widely accepted that the prebiotic pathway of oxygen production in the Earth primitive atmosphere was via vacuum ultraviolet (VUV) photodissociation of CO
2 and subsequent recombination of two O atoms.
In contrast, the photodissociation of H2O, one of the dominant oxygen carriers, has long been assumed to proceed mainly to produce hydroxyl (OH)- and hydrogen (H)-atom primary products, and its contribution to oxygen production is limited.
Credit: DICP
Studying the creation and evolution of sulfur-containing compounds in outer space is essential for understanding interstellar chemistry. CS2 is believed to be the most important molecule in comet nuclei, interstellar dust, or ice cores. CS and S2 are the photodissociation fragments of CS2.
Forty years ago, the emission spectra of only CS and S2 species, and not those of CS2 species, were observed from several comets by the International Ultraviolet Explorer satellite. The photodissociation mechanism of CS2 molecules remains unclear, and S2 fragments have not been experimentally observed before.
Recently, a team led by Prof. YUAN Kaijun from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS), in cooperation with Prof. WANG Xing an s group from the University of Science and Technology of China, observed the C+S2 product channel from CS2 photodissociation for the first time using a home-made Time-Sliced Velocity Map Ion Imaging (TS-V