By treating gaseous,
liquid, or solid fluorides with UV-photolyzed
O2/F2 mixtures and by treating solid oxides
with UV-photolyzed F2 (or O2/F2 mixtures)
in liquid anhydrous HF at ambient temperature, we investigated the
possibility of the preparation of O2MIIIF4 (M = B, Fe, Co, Ag), O2MIVF5 (M = Ti, Sn, Pb), (O2)2MIVF6 (M = Ti, Ge, Sn, Pb, Pd, Ni, Mn), O2MIV
2F9 (M = Sn), O2MVF6 (M = As, Sb, Au, Pt), O2MV
2F11 (M = Pt), O2MVIF7 (M = Se), (O2)2MVIF8 (M = Mo, W), and O2MVIIF8 (M =
I). The approach has been successful in the case of previously known
O2BF4, O2MF6 (M = As,
Sb, Au; Pt), O2GeF5, and (O2)2(Ti7F30). Novel compounds O2GeF5·HF, α-O2Sn2F9 (1-D), and the HF-solvated and nonsolvated forms of β-O2Sn2F9 (2-D) were synthesized and their
crystal structures determined using single-crystal X-ray diffraction.
The crystal structures of all of these materials arise from the condensation
of octahedral MF6 (M = Ge, Sn) units. The anion in the
crystal structure of O2GeF5·HF is comprised
of infinite ([GeF5]−)∞ chains of GeF6 octahedra that share common vertices.
The HF molecules and O2
+ cations are located
between the chains. The crystal structure of α-O2SnF9 (1-D) is constructed from [O2]+ cations and polymeric ([Sn2F9]−)∞ anions which appear as two parallel infinite
chains comprised of SnF6 units, where each SnF6 unit of one chain is connected to a SnF6 unit of the
second chain through a shared fluorine vertex. The single-crystal
structure determination of [O2][Sn2F9]·0.9HF reveals that it is comprised of two-dimensional ([Sn2F9]−)∞ grids
with [O2]+ cations and HF molecules located
between them. The 2-D grids have a wavelike conformation. The ([Sn2F9]−)∞ layer
contains both six- and seven-coordinated Sn(IV) atoms that are interconnected
by bridging fluorine atoms. A new, more complex [O2]+ salt, O2[Hg(HF)]4[SbF6]9, was prepared. In its crystal structure, the Hg atoms bridge
to SbF6 units to form a 3-D framework. The O2
+ cations are located inside the voids while the HF molecules
are bound to Hg atoms through the F atom. Attempts to prepare several
chlorine analogues of O2
+ fluorine salts (i.e.,
O2TiCl5 and O2MCl6 (M
= Nb, Sb)) failed.