本篇以分子動力模擬方法研究LiBF4於Propylene carbonate(PC)及PC /Trimethyl phosphate(TMP)混合液在溫度298 K之擴散、導電、配位與集結性質，並與LiPF6-PC比較。

　　模擬所得之鋰離子、氟原子及溶劑之擴散係數與NMR測量值頗為接近。此外，比導電度之模擬值也與實驗傾向一致。模擬結果顯示，鋰鹽濃度高有利於離子對的形成，但不利於鋰離子與溶劑之配位。當鋰鹽濃度高時，正負離子互相結合的現象愈加明顯，造成離子群內之平均離子數增加，且自由離子比率遞減。難燃之TMP加入後，可當成路易氏鹼，增強與鋰離子之鍵結，因抑制離子對的形成，因而改善溶液之導電度。

　　由於BF4-離子中氟原子之部份電荷比PF6-者高，故BF4-較能吸引鋰離子形成離子對，使得LiPF6-PC系統之導電度優於LiBF4-PC者，此與實驗結果相符。

　Molecular dynamics simulations have been used to study the diffusivity, conductivity, coordination and association properties for LiBF4 in Propylene carbonate (PC) and PC/Trimethyl phosphate (TMP) at 298 K. The results were compared with those of LiPF6-PC system.

　The simulated diffusion coefficients of Li+、F and H atoms agree with the NMR measurements. In addition, the computed specific conductivities have the same trend with experiment. It was shown that the high salt concentration facilitates the ion pair formation, but decreases the solvent coordination. At high salt concentrations, the association between Li+ and anion are serve which increases the average cluster size and reduces the fraction of free ions.As fire-resistant agent TMP, a Lewis base,is added,it binds strongly with Li+ ion, therefore suppressing the ion-pair formation and improving the conductivity.

　Since the partial charge of fluorine atom in BF4- is higher than that of PF6-, BF4- arrarcts Li+ more favorably to form ion-pair, leading a superior conductivity to LiPF6-PC system,which is in accord with experiment.

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