Details

Autor(en) / Beteiligte

• Park, Sungjun
• Choi, Jungkweon
• Ki, Hosung
• Kim, Kyung Hwan
• Oang, Key Young
• Roh, Heegwang
• Kim, Joonghan
• Nozawa, Shunsuke
• Sato, Tokushi
• Adachi, Shin-ichi
• Kim, Jeongho
• Ihee, Hyotcherl

Titel

Fate of transient isomer of CH2I2: Mechanism and origin of ionic photoproducts formation unveiled by time-resolved x-ray liquidography

Ist Teil von

• The Journal of chemical physics, 2019-06, Vol.150 (22), p.224201-224201

Ort / Verlag

Melville: American Institute of Physics

Erscheinungsjahr

2019

Quelle

美国小型学会期刊集（AIP Scitation平台）

Beschreibungen/Notizen

• Diiodomethane, CH2I2, in a polar solvent undergoes a unique photoinduced reaction whereby I2− and I3− are produced from its photodissociation, unlike for other iodine-containing haloalkanes. While previous studies proposed that homolysis, heterolysis, or solvolysis of iso-CH2I–I, which is a major intermediate of the photodissociation, can account for the formation of I2− and I3−, there has been no consensus on its mechanism and no clue for the reason why those negative ionic species are not observed in the photodissociation of other iodine-containing chemicals in the same polar solvent, for example, CHI3, C2H4I2, C2F4I2, I3−, and I2. Here, using time-resolved X-ray liquidography, we revisit the photodissociation mechanism of CH2I2 in methanol and determine the structures of all transient species and photoproducts involved in its photodissociation and reveal that I2− and I3− are formed via heterolysis of iso-CH2I–I in the photodissociation of CH2I2 in methanol. In addition, we demonstrate that the high polarity of iso-CH2I–I is responsible for the unique photochemistry of CH2I2.