Hexafluorophosphate, PF

The lanthanide triflates may also be obtained by the addition of triflic acid to lanthanide carbonates in ethanol or acetonitrile [18]. Filtration and concentration of the filtrate yield a solid salt which is washed with solvent. Lanthanide salts of poorly coordinating anions such as PFg, BF4 or BiCftHs) have been also used in the synthesis of lanthanide complexes as starting materials. Adducts of acetonitrile with europium tetrafluoroborate (BF4) and hexafluorophosphate (PF ) have been prepared [19]... 

Theoretically, a trillion or more ionic liquids are possible. To make an ionic liquid, researchers can select it from dozens of small, negatively charged ions, such as hexafluorophosphate ([PFs]-) and tetrafluoro-borate ([BF4]-), and hundreds of thousands of larger, positively charged ions, such as l-hexyl-3-methylimida-zolium or l-butyl-3methylimidazolium. 

Initial investigations from the early 1990s onwards have provided [53] a reliable means by which the tetracationic cyclophane CBPQT4+ and a number of [2]- and [3]catenanes can be self-organized at the air-water interface. Although an amphiphilic character is usually required to obtain a Langmuir monolayer, it is obvious that the catenane 174+ - when associated with four hexafluorophosphate counterions - possesses few bipolar properties. This realization is reflected in the fact that the hexafluorophosphate (PF ) salt of 174+ forms brittle monolayers that are difficult to reproduce. The amphi-... 

According to their composition, ILs can be briefly grouped into aprotic, protic, and zwitterionic types, as shown in Figure 2.49 [498]. To date, the ILs used in ESs represent only a very small portion of the large family of ILs. The investigated ILs for ESs are commonly based on imidazolium, pyrrolidinium and ammonium, sulfonium, phosphonium cations, etc (Figure 2.50). Typical anions of ILs include tetrafluoroborate (J3F4 ), hexafluorophosphate (PF e ), bis(trifluoromethanesulfonyl) imide (TFSL), bis(fluorosulfonyl)imide (FSl), and dicyanamide (DCA). 

These metallic features have been reported in conducting versions of both PAN and PPy. The ability to process PAN doped with camphorsulfonic acid (CSA) from solution [22,76] has resulted in freestanding films with high conductivity 100—400 S/cm) [44,77] that span the IMT even at low temperature [45,75]. Some samples of electrochemically prepared PPy doped with hexafluorophosphate (PFs) are metallic to millikelvin temperatures [29,41,42]. However, when PPy is synthesized using different dopants or at high temperatures, the materials are more disordered and show insulating behavior [28-30]. Similar results are reported in the Kterature for conducting polyacetylene [41,42]. 

Non-aqueous electrolytes containing salts of alkyl substituted cyclic delocalized aromatic cations. Certain polyatomic anions, preferably PF " are dissolved in high conducting organic liquids such as alkyl carbonate solvents or liquid SC at concentrations >1M. Salt of l-ethyl-3-methylimidazolium and hexafluorophosphate (PF -) is reported to have high conductivity of less than 13 mS/cm, electrochemical stability >2.5 V, and high thermal stability >100°C. High capacitance of >100 F/g is obtained when used with activated carbon electrodes. 

Most ILs used for extraction are odorless and colorless [14]. Thus, multiple methods have been developed to remove color and odor impurities from ILs [14]. We will review some of these methods in this section. First, we will review literature methods for decolorizing ILs. For example, Earle and co-workers used a special column containing charcoal particles and silica gel to investigate the discoloration of ILs [22]. Earle et al. found that this special column worked particularly well with ILs that contained bistriflimide ([NTf2] ), tetrafluoroborate ([BF4] ), and hexafluorophosphate ([PF ] ) [22]. Moreover, Earle et al. found that this method worked better on the final IL than the corresponding halide salt... 

Ionic liquids are salts that have, per definition, a melting point below 100 °C. If their melting point is below room temperature they are called room temperature ionic liquids (RTIL). The latter have attracted much interest in recent years as novel solvents for reactions and electrochemical processes [116]. Some of these liquids are considered to be green solvents [117]. The most commonly used liquids are based on imidazoHum cations like 1-butyl-3-methylimidazolium [bmim] with an appropriate counter anion like hexafluorophosphate [PFs]. Many ionic liquids are known to accelerate reactions. In most cases, achiral ionic liquids are applied and have been reviewed [116], Here, the few examples of chiral ionic liquids (CILs) as catalysts are discussed. 

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