Simple Inorganic Fluorides

BaFBr is an important storage phosphor material which forms solid solutions and gives rise to nonstoichiometric compositions such as (BaF)i iBro.g. The principal F MAS NMR resonance in BaFBr occurs at 150.9 ppm but the non-stoichiometric sample shows an additional line at 145.3 ppm with an intensity of 9%. The similarity of this intensity to the 10% excess fluorine in the sample led to the assignment of this resonance to fluorine on the antisites (the bromine sites) (Schweizer etal. 1998). 

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Gne of the most interesting simple inorganic compounds reported in recent years is peroxodisulfuryl difluoride, F—SO2—02—S02—F (mp, —55° C bp, 67° C). This is both a peroxo compound and an acid fluoride but prepared by the fiuorination of sulfur trioxide. The compound can be... 

SF4 forms adducts with main group inorganic fluorides, and these have been variously described as simple Lewis acid-base systems (with SF4 behaving as the base) or as ionic systems such as [Sp3]+ [BF4] . The reactions of SF4 with organic molecules have been widely studied. The most important reaction is the conversion of a carbonyl gronp to a diflnoride (eqnation 51). 

Although tetraalkylammonium salts, suitable as ion-pair reagents for ion-pair chromatography of simple inorganic anions, are predominantly employed in combination with polymer phases [24,25], they may equally be used when applying chemically bonded reversed phases [16,26]. The separation of inorganic anions on LiChrosorb RP18 shown in Fig. 5-13 serves as an example. In contrast to polymer phases, the fluoride determination is a problem because fluoride is poorly retained on chemically bonded reversed phases. If direct conductivity detection is applied, a quantitative evaluation of the fluor-... 

A great variety of compositions were tested. One group of solutions contained only simple inorganic salts such as sulfates, fluorides, chlorides, fluoborates, pyrophosphates, and cyanides, which may be treated as weak ligands with the... 

Inorganic salts that contain halogens are usually soluble. They commonly occur as simple, single, negatively charged anions in soil. There are two common exceptions to this generalization. First, fluorine is commonly found bonded to phosphate in insoluble minerals called apatites, which are calcium phosphate fluorides. 

The essence of this theory on the mechanism of ECF is that reaction occurs via inorganic fluorinating agents generated at the anode these include nascent fluorine, molecular fluorine, or its loose complexes with nickel fluorides, and simple or complex forms of high valence nickel fluorides [62,65,169,178,179]. However, until the precise nature and structure of the active nickel anode surface is characterised the position remains a matter for conjecture. 

Up to now, only two one-dimensional zirconium phosphates have been reported. One is [enH2][Zr(HP04)3] [16], and the other is zirconium phosphate fluoride [enH2]i.5[Zr(P04)(HP04)F2] [13] with double-stranded chains. The simple models of one-dimensional chain inorganic polymers are shown schematically in Figure 2. ZrPO-3 has a chain- structure similar to the one-dimensional aluminum phosphate, [A1P208H]2 [29]. 

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