secondary cells with lithium anodes and immobilized fused_salt

118.
fom such salts as cS+m8- have been reported, but the fluorine exchange which occurs
between W and IFj in.the gas phase may involve a HIF8 or a IF#E'2 intermediate.
The halogen fluoride, oxides of major. interest are C102F and C103F, but
Br02F, I@2F and IFSO ha>re .been characterized. Only perchloryl fluoride, ClO3F, .iscomerciall::
available. Chloryl fluoride, C102F, is readily prepared by allowing
ClFs or ClF5 to stand with excess of a chlorate or chlorite salt in a Monel cylinder:
2CD3 + SI'iaC105
250 3 3C102F + 3NaF + Clg + 1.502
.
C1F5 + 3iTaC102 250 > 2C102F + 3NaF + C12 + 02
me 02 and C12 are removed at -80O.) me C102F is also formed by the reaction of
cLF3 or C1Fg with traces of moisture, but is in turn readily hydrolyzed with additi0221
water.
I
,The C102F is isoelectronic.with PF3 and SF20 and should have, approximately
the same structure, i.e., a tetrahedral arrangement with an ,'electron pair at
one apex. ??le I9F AT4R shows the fluorine atom far downfield, 6 = -332 ppm. This
structure makes C102F an extremely reactive oxidizer. It is in turn fluorinated
only witt diffic:dty to ClF5. The C102F undergoes the fluoride abstraction reaction
to g;:;c :;:;2i,le salts such as C102+AsF6-, but efforts to form such salts as Cs'ClF20;
have not beer: successful. Pyrolysis of C102F at 300' and 0.5 atm. pressure gives
C1F acd 02 apparently via an intermediate ClFO species.
Perchloryl fluoride has a closed tetrahedral structure with the approximate
:xrometers:
The
C1-F, 1.55-1.60 1; C1-0, 1.40 1, dipole moment 0.023 D.
shows the fluorine at fl = -287 ppm. The structure of C103F gives it con-
siderable kinetically d'erived stability and it is relatively unreactive at mild temperatures,
e.g., it does not hydrolyze, or react with sodium. Above 150' C103F is a
potect oxidizer for most organics and.attacks many metals in the presence of moisture.
Attempts to react ClO3F with fluoride acceptors such as kF5 have not led to
stable salts, but the AlCl3-catalyzed reaction .of C103F with aromatics (to give
Arc105 compounds) likely ivvolves an intermediate ClO3' ion. No reaction between
CsF 2nd ClO3F has been effected and C103F is'quite resistant to fluorination. With
iX5, C103F is cocverted to NH4+ifHC103-, from which metal salts such as KNIIClO3 ahd
Kr,l.IClO3 can be prepared. All of these salts are shock sensitive. Perchloryl fluori$e
is generally quite soluble without reaction with other oxidizers and has a
-small (0.5-5 g/liter) solubility in organic solvents and water.
I' The
Bromyl fluoride SrO2F (formed by the reaction KBrO3 or BrO2 and BrF5 at
-59") is thermodynamically unstable and has been studied very little. Of the reported
iodine fliioride oxides, only IFSO appears to be unequivocally established as
a molecular entity. It is readily formed by reaction of IF7 with traces of moisture
or with glass and has a relatively low reactivity because of the nearly octahedral
structure. The remaining iodine fluoride oxides, IF30, I02F and I%F are all white
crystalline solids and may not be molecular entities. The "IF3O" and "I02F" can be
prepared by reactir.g 1205 respectively with IF3 and F2. The pyrolysis of IF30 gives
I02F arid IF5 end the 03ser:red reversibility of this .reaction suggested the ionic
strilcture IO2 IF6- for IFQO. The I0gF.may exist in a bridged form or possibly in
the ionic form, 102+TF262:, since stable .salts of both of these ions are formed.
,103F (formed by fluorination of periodic acid in HF) is reported to undergo
hydrolysis slowly and- thus may'iwfact be structurally analogous to Cl03F.
.