Design and Control of Graphite Intercalation Reactions in Liquid Hf.

1.不挥发性氟化物-GIC：我们发现了一种新的合成不挥发性氟化物的途径，即在氟气饱和的液体AHF中，插入不挥发性氟化物的物种。插层反应是通过氟代金属酸盐取代氟化氢进行的：C_x + 1/2F_x + HF -> C_xHF_2 + MF^-2。该方法合成了一系列以SnF_4，PbF_4，CrF_4，SbF_4，RhF_3和LiBF_4.2等不挥发性氟化物为基础的新型C_xMF_y。对C_SnF_5晶体的X射线旋进谱的研究<30>表明，这种插入物的晶格与石墨的α参数不相称。用EXAFS方法确定了锡在SnF_4和C_ SnF_5中的局域环境<30>。第一配位层由氟离子的轴向扁平八面体形成。在<11OMEGA>4.2&lt;T&lt;293 K的温度范围内对C_SnF_5进行了~（40）Sn_Mo ~（40）“穆斯堡尔共振研究<30>。在室温下，观察到单一的。随着温度的降低，出现了相当大的展宽，在160 - 140 K之间出现了一个由强四极分裂引起的双重峰。这些结果表明客体物种的二维相变.用光学测量方法研究了第2阶段C_xCrF_y和C_xRhF_y GIC中的电荷转移。电荷转移系数f=0.50和f=0.59每个插层物种已被确定从反射率数据使用的Blinowski-Rigaux模型。费米能也已从光学测量中评估。C_xCrF_y和C_xRhF_y的E_F值分别为0.94和0.89eV。

1. Involatile Fluoride-GIC.We have found a new synthetic pathway to involatile fluoridebased in liquid AHF which is saturated with fluorine gas and the species to be intercalated. The intercalation reaction proceeds through the substitution of bifluoride by fluorometallate as follows ;C_x + 1/2F_x + HF -> C_xHF_2 + MF^-_2An attractive feature of this method is that the stage can be controlled by changing the concentration of fluorometallate in ahf. This preparative method has been giving a series of new C_xMF_y based on involatile fluorides, SnF_4, PbF_4, CrF_4, SbF_4, RhF_3, and LiBF_4.2. The study of X-ray precession patterns of a crystal of composition C_<30>SnF_5 has shown that the lattice of the intercalate is incommensurate with the a-parameter of graphite. The local environment of tin in both SnF_4 and C_<30>SnF_5 has been determined from EXAFS. The first coordination shell is formed of axially flattened octahedra of fluoride ion.3. A ^<11OMEGA>Sn Mo^^"ssbauer resonance investigation has been performed over the temperature range 4.2<T<293K on C_<30>SnF_5. At room temperature, a single is observed. A sizable broadening occurs with decreasing temperature, and between 160K and 140K a doublet appears owi ng to a strong quadrupole splitting. These results suggest a two-dimensional phase transition of the guest species.4. Charge transfer has been evaluated in stage-2 C_xCrF_y and C_xRhF_y GICs by optical measurements. Charge transfer coefficients f=0.50 and f=0.59 per intercalated species have been determined from reflectivity date using the Blinowski-Rigaux model. The fermi energies have also been evaluated from the optical measurements. E_F values are 0.94 and 0.89eV for C_xCrF_y and C_xRhF_y, respectively.