| Summary: | 碩士 === 國立成功大學 === 化學系專班 === 95 === Under the neat ionic liquid condition, it is observed that the cation and anion diffused respectively. In recently, there were also papers about cation’s 1H and 19F NMR spectrum pointed out that the HAP (hyper anion preference) is more than the HCP (hyper cation preference) under the different temperature and the different organic solvent ratio.
Which reason actually affects the intermolecular relative function in the ionic liquid and the solvent? And which reaslly affects the hyper anion preference, is the major research motive of this paper. We use the B3LYP/6-31G* method to calculate the solvent molecule and binding energy tendency between the cation and anion. And using the computational E(2) value to explaine the NMR experimental T1-19F and T1-1H results (relaxation time). The first part of this paper (adding solvents to the ionic liquid system), the computational results meet the NMR experimental results. In the second part of this paper (hyper ion preference), the theoretical calculation results are unable to explain the results of the NMR experiment. Regarding this unable explained phenomenon, we try to use the following formula to explain that,
�� G = H－TS ……… (1)
When G = 0, H = TS
�� T = H/S ……… (2)
Where, H is equal to the theoretical calculated stability energy (SE). In formula 2, the temperature (T) is inverse proportion with entropy change (S) but direct proportion with enthalpy change (H). Thought the calculated H values have not much difference between hyper anion and hyper cation, we explain that regarding the next conclusion: Under the gaseous state ionic liquid, the entropy change (S), in fact, is the most influence.
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