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摘要: |
利用团簇模型研究了二氧化碳对质子化甲醇的溶剂化作用.H+(CH3OH)(CO2)n+(n=1~7)的量子化学计算结果表明,需要3个或4个二氧化碳分子完成甲醇的羟基第一溶剂层.除了氢键,二氧化碳分子间的相互作用对大团簇的稳定性也起到了重要的作用.在这些溶剂化作用的早期阶段,不容易发生质子从甲醇到二氧化碳的转移过程.模拟的红外光谱揭示了自由O-H伸缩振动、氢键作用后的O-H伸缩振动、以及二氧化碳的O-C-O伸缩振动频率是研究质子化甲醇溶剂化过程的灵敏探针. |
关键词: 甲醇,二氧化碳,溶剂化,红外光解离光谱,量子化学计算 |
DOI:10.1063/1674-0068/28/cjcp1507146 |
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Early Stage Solvation of Protonated Methanol by Carbon Dioxide (cited: 1) |
Zhi Zhao,Xiang-tao Kong,Xin Lei,Bing-bing Zhang,Ji-jun Zhao,Ling Jiang*
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Abstract: |
The solvation of protonated methanol by carbon dioxide has been studied via a cluster model. Quantum chemical calculations of the H+(CH3OH)(CO2)n+(n=1-7) clusters indicate that the rst solvation shell of the OH groups is completed at n=3 or 4. Besides hydrogen-bond interaction, the CCO2…OCO2 intermolecular interaction is also responsible for the stabilization of the larger clusters. The transfer of the proton from methanol onto CO2 with the formation of the OCOH+ moiety might be unfavorable in the early stage of solvation process. Simulated IR spectra reveal that vibrational frequencies of free O-H stretching, hydrogen-bonded O-H stretching, and O-C-O stretching of CO2 unit a ord the sensitive probe for exploring the solvation of protonated methanol by carbon dioxide. IR spectra for the H+(CH3OH)(CO2)n+(n=1-7) clusters could be readily measured by the infrared photodissociation technique and thus provide useful information for the understanding of solvation processes. |
Key words: Methanol, Carbon dioxide, Solvation, Infrared photodissociation spectroscopy, Quantum chemical calculation |