中文摘要：

以具有支链结构的溴代仲丁烷作为烷基化试剂，在微波辐射下采用两步法合成了1-仲丁基-3-甲基咪唑六氟磷酸盐（[s—bmim][PF6]）离子液体．在配比为V（水）：V（乙醇）：V（甲苯）=0．16：2．84：7的混合溶剂体系中，培养出品型完整的长约11mm的离子液体大单晶体．通过单晶体X衍射研究了[s—bmim][PF6]的晶体结构．[s—bmim][PF6]属于三斜立方晶系，空间群为P2（1）／m，晶胞参数为n=0．9042（4）nm，b=0．8213（3）nm，C=0．9775（4）nm，γ=116．618°（6），Z=2，V=64．909（4）nm^3，D，=1．454g／cm^3，μ=0．265mm^-1，F（000）=292．在[s—bmim][PF6]晶体结构中，阴阳离子间的离子键仍然是主要的，同时还存在氢键和阳离子-阳离子间的非键斥力作用．研究结果表明，[s—bmim][PF6]的支化烷基结构对其晶体有效堆积、熔点、液程范围以及热分解温度等性质具有重要影响．

英文摘要：

In this paper, 1-sec-butyl-3-methylimidazolium hexfluorophosphate （ [ s-bmim ] [ PF6 ] ） was synthesized with the aid of microwave. Large single crystals were formed in the water-ethanol-toluene system [ V（ water）： V（ ethanol） ： V（toluene） = 0. 16： 2.84：71. The large single crystals are stable under the air and moisture, with the maximum length of 11 mm. The crystal structure was determined by X-ray diffraction. [ s-bmim ][ PF6 ] crystallizes in the monoclinic space group P21/m, with unit-cell parameters a = 0. 9042 （4） nm, b=0.8213（3） nm, c=0.9775（4） nm, T=116.618°（6）, Z=2, V=64.909（4） nm3, Dc=1.454 g/cm3,μ =0. 265 mm^-1 , F（000） =292, the final R =0. 0998, wR =0. 2656. In the structure, the cations and anions can not form neutral ion pairs owing to the interionic interactions such as the dominant Coulombic attraction, the weak hydrogen bonds and the non-chemical-bond tension of cation-cation. Moreover, it was found that introducing the sec-butyl chain could change the asymmetry of cations and inhibit the rotation of the alky chains of [ s-bmim ] [ PF6 ]. The branched structure leads to the void space filling in the crystal stacking and high lattice energy. Finally, the thermal stability of [ s-bmim ] [ PF6] was discussed.