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Bis(tetraphenylarsonium) hexafluoridotechnetate(IV) dihydrate: preparation, structure and spectroscopic analysis
Samundeeswari Mariappan Balasekaran1, Frederic Poineau1
1Department of Chemistry and Biochemistry, University of Nevada Las Vegas, 4505 South Maryland Parkway, Las Vegas, Nevada 89154, USA.
Abstract:
Reports of quadrivalent transition-metal fluoride salts containing bulky organic cations are limited. In this context, we prepared the bis(tetraphenylarsonium) hexafluoridotechnetate(IV) dihydrate salt, (C24H20As)2[TcF6]·2H2O, by a cation metathesis reaction of (NH4)2[TcF6] in water. This is the first report of an arsonium salt of the hexafluoridotechnetate(IV) dianion. (AsPh4)2[TcF6]·2H2O crystallizes in the triclinic space group P-1. The [TcF6]2- anion adopts a slightly distorted octahedral geometry with an average Tc-F bond length of 1.933 Å. The cyclic voltammogram of (AsPh4)2[TcF6]·2H2O in CH3CN shows a one-electron reversible oxidation wave at 1.496 V.
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