本篇以分子動力模擬的方法，討論溫度（313、343 K）與LiBF4濃度（0、1.0、1.5與2.0 M）之改變對於EMIBF4 /LiBF4混合液之離子導電性、配位與結合之影響。首先由均方位移圖求得物種H、Li＋與F之擴散係數，並由Nernst-Einstein公式與自由離子機率計算比導電度。再由徑向分佈函數圖探討離子間的交互作用力，並了解其配位與集結之情形。

　　由模擬結果可知，擴散係數與比導電度值隨LiBF4濃度的增加而遞減，且隨溫度的升高而遞增，與實驗結果相符。與EMI＋之酸性氫原子形成氫鍵之BF4－之氟原子數，在溫度313 K時約為2.23～2.36，視LiBF4濃度而定。其值隨溫度之增加而遞減。

　　EMI＋質心與Li＋周圍之BF4－離子配位數，在313 K、1.0 M時，分別為8.27與2.77，其值隨濃度而遞增。溫度的增加有利於Li＋周圍之BF4－離子之配位，但對於EMI＋離子幾乎沒有影響。溶液中形成各式各樣的離子群，如單體（Li＋、EMI＋或BF4－）、雙體（LiBF4或EMIBF4），三體（[Li(BF4)2]－、[EMI(BF4)2]－、[Li(EMI)(BF4)]＋、 [Li2BF4]＋、或[(EMI)2BF4]＋）等，其比率隨濃度與溫度之變化可經由本模擬求得。

　　Molecular dynamic simulation method has been employed to study the influences of the temperature（313, 343 K）and LiBF4 concentration（0, 1.0, 1.5, 2.0 M）on the ionic conductivity, coordination and association of the EMIBF4/LiBF4 binary system. The diffusion coefficients of the species H, F, Li＋ were computed firstly from the plot of the mean-squared displacement. With the aid of Nernst-Einstein equation and the calculated free ion probability, the specific conductivity of the system was estimated. The radial distribution functions were then analyzed to understand the ionic interaction, coordination and aggregation within the system.

　　It’s known from the simulation that the diffusion coefficient and specific conductivity decreases with the increasing LiBF4 concentration and decreasing temperature, which is in accord with experiment. The number of the hydrogen-bond forming F atoms of BF4－ around the acidic hydrogen atom of EMI＋ is between 2.23 and 2.36 at 313 K, depending on concentration. The number decreases with the increasing temperature.

　　At 313 K and 1.0 M, the number of coordinating BF4－ anions around Li＋and EMI＋ cation is 2.77 and 8.27, respectively. The coordination number increases with the increment of LiBF4 concentration. The increase of temperature facilitates the coordination of BF4－ around Li＋, but has virturally no effect for EMI＋. Various forms of ionic clusters were found in the solution, such as monomer（Li＋, EMI＋, BF4－）, dimmer（LiBF4, EMIBF4）, trimer（[Li(BF4)2]－, [EMI(BF4)2]－, [Li(EMI)(BF4)]＋, [Li2BF4]＋ or [(EMI)2BF4]＋）, etc. The variations of their fractions with LiBF4 concentration and temperature were obtained from the present simulation.

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