Photoinduced reaction of methylpolyynes H(C≡C)_nCH_3 (n=5-7) and polyyne H(C≡C)_5H with I_2 molecules
Photoinduced reaction of methylpolyynes H(C≡C)_nCH_3 (n=5-7) and polyyne H(C≡C)_5H with I_2 molecules
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甲基多炔H(C^C)_nCH_3 (n=5-7)和多炔H(C^C)_5H与I_2分子的光诱导反应
DOI：
10.1140/epjd/e2012-30545-x
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发表时间：
2012
期刊：
影响因子：
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通讯作者：
Tomonari Wakabayashi
中科院分区：
文献类型：
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作者：
Yoriko Wada;Kazunari Koma;Yuma Ohnishi;Yuya Sasaki;Tomonari Wakabayashi
在碘分子存在下，甲基多炔H（C_CN）_nCH_3（n= 5-7）在正己烷中被光照射，通过紫外吸收光谱的系统变化，证实了一系列分子络合物H（C_CN）_nCH_3（I_6）（n= 5-7）的形成。为了研究反应机理，用532 nm的连续激光束照射氢封端的聚炔、H（C_（10）C）_5 H和I_2分子的己烷溶液，然后记录其紫外吸收光谱，得到聚炔C_10H_2的时间衰减曲线。在C10 H2浓度约为7μmol L ~（-1）时，C10 H2的衰减曲线中的反应速率随I_2浓度（8.2-126μmol L ~（-1））和激光功率（0.34-6.2 mW）的增加而增加。基于动力学模型，C10 H2的降解与多炔-碘分子复合物H（C = C）5 H（I6）的形成竞争。复合物的形成被认为是有效的条件下，I2浓度的数量级高于C10 H2浓度，因为这抑制了降解过程。
Methylpolyynes, H(C≡C)nCH3(n= 5-7), were photo-irradiated under the presence of iodine molecules in hexane to confirm the formation of a series of molecular complexes, H(C≡C)nCH3(I6) (n= 5-7), by systematic changes in their UV absorption spectra. In order to investigate the reaction mechanism, solutions of hydrogen-capped polyyne, H(C≡C)5H, and I2molecules in hexane were irradiated with a cw-laser beam at 532 nm, then their UV absorption spectra were recorded to obtain temporal decay profiles for the polyyne C10H2. At C10H2concentrations of about 7μmol L-1, the rate of reaction in the decay profile for C10H2increased with increasing I2concentration (8.2–126μmol L-1) as well as with increasing laser power (0.34–6.2 mW). Based on a kinetic model, the degradation of C10H2was shown to compete with the formation of the polyyne-iodine molecular complex, H(C≡C)5H(I6). The formation of the complex was found to be efficient under the condition that the I2concentration is orders of magnitude higher than the C10H2concentration as this suppresses the degradation process.