本篇以分子動力模擬方法研究離子液體1-methyl-3-ethylimidazolium trifluoromethanesulfonate (簡稱EMICF3SO3)與1-methyl-3-ethylimidazolium bis(trifluoromethanesulfonimide) (簡稱EMITFSI)之混合液在溫度363 K時的擴散、導電、配位及離子集結特性，並與文獻之實驗結果比對。
模擬之導電度和擴散係數值與實驗值相當接近。模擬結果顯示，EMI+離子之移動速度較CF3SO3-與TFSI-離子快，對導電度貢獻較大。這些離子的擴散速率並不因EMICF3SO3含量之改變而有明顯變化，顯示導電度之增加並非由擴散速率改變所造成。在混合溶液中EMI+離子距離TFSI-較近，其離子對作用能量也較大，故易形成EMI+TFSI-離子對。當EMICF3SO3含量增加時，大多數CF3SO3-離子以自由離子形式出現，使得帶電粒子增加，進而增加導電度。離子集結所形成之帶電離子團也能幫助導電，但離子群之分析顯示，離子團大多以陰、陽離子1:1的形式組成，對導電度貢獻極小。
純EMITFSI系統之EMI+周圍TFSI-離子數介於6至12之間，其中以9最有可能。只有EMICF3SO3存在時，與EMI+離子周圍之CF3SO3-配位數為12。EMI+周圍第一配位殼層內之CF3SO3-離子數隨EMICF3SO3之含量增加而遞增，但TFSI-離子數則遞減。這可能是因為EMI+離子周圍之空間有限，當配位半徑固定時，體積小的CF3SO3-離子能填得比TFSI-離子多。
每個離子群所含平均離子數隨著EMICF3SO3含量之增加而遞減，在EMICF3SO3莫耳分率為0.8時達到最小(2.01)。但純EMICF3SO3之平均離子數反而最大(2.46)，此因CF3SO3- 離子之體積較小，能盡量在EMI+周圍堆積，使結合更嚴重。平均自由離子機率隨EMICF3SO3含量之增加而遞增，在EMICF3SO3莫耳分率為0.8時最為明顯 (約0. 267)。但對於純EMICF3SO3系統，平均自由離子機率遽降為0.195，此證明離子液體混合後帶電粒子增加。

Molecular dynamics simulations have been used to study the diffusivity, conductivity, coordination and aggregation properties of the binary mixture of 1-methyl-3-ethylimidazolium trifluoromethanesulfonate (EMICF3SO3) and 1-methyl-3-ethylimidazolium bis(trifluoromethanesulfonimide) (EMITFSI) at 363K. The results were compared with the literature data.
The simulated conductivities and diffusion coefficients are close to those from the experiment. The simulations show that the EMI+ ion moves faster than CF3SO3- and TFSI- ions, giving higher contribution to conductivity. The diffusion rate of these ions, however, does not change much with the variation of EMICF3SO3 content, which indicates that the increase of conductivity does not arise from the change of diffusion rate. Since EMI+ ion is closer to TFSI- ion than CF3SO3- ion, and the ion pair energy between EMI+ and TFSI- ions is also larger, it’s relatively easy to form the EMI+TFSI- ion pair. When the EMICF3SO3 content increases, most of the CF3SO3- ions are free to migrate through out the liquid, causing the charged particle to increase, which leads to the enhanced conductivity. The charged ion cluster formed in the solution should facilitates the electric conduction, but it’s shown cations and anions that ion clusters mostly consist of 1:1, leading the conductivity contribution to be minimum.
The number of coordinating TFSI- ions around EMI+ in pure EMITFSI system is between 6 and 12, with a most probable value of 9. On the contrary, the most probable number of coordinating CF3SO3- ions around EMI+ is 12 in pure EMICF3SO3 system. With the increase of EMICF3SO3 content, the number of coordinate CF3SO3- ions around EMI+ increases, but that for TFSI- decreases. This possibly is due to the limited space around EMI+. The size of CF3SO3- ion is smaller than that of TFSI-, therefore it can be packed more around EMI+ ion.
The average number of ions per cluster decreases with the increasing EMICF3SO3 content, which is the smallest (2.01) at a EMICF3SO3 fraction of 0.8. For the pure EMICF3SO3 system, this value reaches the maximum (2.46). This is due to the small size of CF3SO3- ion, which can be packed closely around EMI+ ion, causing the ionic association. The average free ion fraction increases with the increasing content of EMICF3SO3, whose value in the highest (0.267) at a EMICF3SO3 mole fraction of 0.8. But for the pure EMICF3SO3 system, this value decreases radically to 0.195, which demonstrates the number of charged particle indeed increases as predicated by Every.

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