Evidence for direct molecular oxygen production in CO2 photodissociation
Evidence for direct molecular oxygen production in CO2 photodissociation
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DOI：
10.1126/science.1257156
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发表时间：
2014-10-03
期刊：
影响因子：
56.9
通讯作者：
Jackson, William M.
中科院分区：
文献类型：
--
作者：
Lu, Zhou;Chang, Yih Chung;Jackson, William M.
二氧化碳(CO2)的光解离长期以来一直被认为是专用于一氧化碳(CO)和氧原子(O)初级产物的。然而，最近的理论计算表明，产生C+O-2的出口通道也应该是能量可及的。本文报道了C(P-3)+O2(X-3 Sigma(-)(G))通道能量阈值附近C(P-3)+O2(X-3 Sigma(-)(G))通道能量阈值附近C(P-3)+O2(X-3 Sigma(-)(G))通道产率为5+/-2%的直接实验证据。我们的结果可能对在二氧化碳浓度较高的大气中产生非生物氧气有一定的意义。
Photodissociation of carbon dioxide (CO2) has long been assumed to proceed exclusively to carbon monoxide (CO) and oxygen atom (O) primary products. However, recent theoretical calculations suggested that an exit channel to produce C + O-2 should also be energetically accessible. Here we report the direct experimental evidence for the C + O2 channel in CO2 photodissociation near the energetic threshold of the C(P-3) + O2(X-3 Sigma(-)(g)) channel with a yield of 5 +/- 2% using vacuum ultraviolet laser pump-probe spectroscopy and velocity-map imaging detection of the C(P-3(J)) product between 101.5 and 107.2 nanometers. Our results may have implications for nonbiological oxygen production in CO2-heavy atmospheres.