Eight salts of [NEt_xMe_(3-x)(i-Pr)][BEt_(4-y)Me_y] (x = 1–3. y = 0, 1.) were prepared to reduce Coulombic interactions in the crystals. These novel ionic plastic crystals exhibited low activation energies for isotropic rotational motion (E_{a rot}) and ion diffusion (E_{a diff}). The lattice constant a in the cubic structure indexed to a CsCl-type was larger than that of the corresponding plastic crystals of [NEt_xMe_(4-x)][BEt_(4-y)Me_y] (nonbranched sample). Solid-state ₁H and ₁₃C nuclear magnetic resonance (NMR) spectra of the salts revealed that both cations and anions undergo isotropic reorientation motions in the plastic crystalline phase. This result is consistent with the differential scanning calorimetry data, which showed that the compounds have large entropy changes at the transition temperature between the ordinal and plastic crystalline phases, except for [NEt₂Me(i-Pr)][BEt₃Me] and [NEt₃(i-Pr)][BEt₃Me].. The E_{a rot} and E_{a diff} values were estimated using ₁H NMR spin-lattice relaxation time (T₁) and electrical conductivity measurements, respectively.

中文翻译：

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具有支链结构的新型离子塑料晶体的固体 1H 和 13C NMR 研究：[NEtxMe（3-x）（i-Pr）][BEt（4-y）Mey] （x = 1–3. y = 0， 1。


[NEt_xMe_（3-x）（i-Pr）][BEt_（4-y）Me_y] （x = 1–3.y = 0， 1。制备以减少晶体中的库仑相互作用。这些新型离子塑料晶体对各向同性旋转运动 （E_{a rot}） 和离子扩散 （E_{a diff}） 表现出低活化能。索引为 CsCl 型的立方结构中的晶格常数 a 大于 [NEt_xMe_（4-x）][BEt_（4-y）Me_y]（非支链样品）的相应塑料晶体的晶格常数 a。盐的固态 ₁H 和 ₁₃C 核磁共振 （NMR） 光谱显示，阳离子和阴离子在塑性结晶相中都经历各向同性取向重新定向运动。该结果与差示扫描量热法数据一致，差示扫描量热法显示，在序相和塑性晶相之间的转变温度下，化合物具有较大的熵变，除了 [NEt₂Me（i-Pr）][BEt₃Me] 和 [NEt₃（i-Pr）][BEt₃Me].. E _{a rot} 和 E_{a diff} 值分别使用 ₁H NMR 自旋晶格弛豫时间 （T₁） 和电导率测量来估计。