Th
e hydroth
ermal r
eaction of MoO
3 with BaH
3IO
6 at 180
es/
entiti
es/d
eg.gif">C for 3 days r
esults in th
e formation of Ba[(MoO
2)
6(IO
4)
2O
4]·H
2O (
1). Und
er similar conditions, th
e r
eaction of Ba(OH)
2·8H
2O with MoO
3 and Ba(IO
4)
2·6H
2O yi
eldsBa
3[(MoO
2)
2(IO
6)
2]·2H
2O (
2). Th
e structur
e of
1, d
et
ermin
ed by singl
e-crystal X-ray diffraction, consists of corn
er-and
edg
e-sharing distort
ed MoO
6 octah
edra that cr
eat
e two-dim
ensional slabs. Contain
ed within this molybd
enumoxid
e fram
ework ar
e approximat
ely
C2v t
etraoxoiodat
e(V) anions, IO
43-, that ar
e involv
ed in bonding with fiv
eMo(VI) c
ent
ers. Th
e two
equatorial oxyg
en atoms of th
e IO
43- anion ch
elat
e a singl
e Mo(VI) c
ent
er, wh
er
eas th
eaxial atoms ar
e es/
entiti
es/mgr.gif">
3-oxo groups and compl
et
e th
e octah
edra of four MoO
6 units. Th
e coordination of th
e t
etraoxoiodat
e(V) anion to th
es
e fiv
e highly
el
ectropositiv
e c
ent
ers is probably r
esponsibl
e for stabilizing th
e substantial anioniccharg
e of this anion. Th
e Ba
2+ cations s
eparat
e th
e lay
ers from on
e anoth
er and form long ionic contacts withn
eighboring oxyg
en atoms and a wat
er mol
ecul
e. Compound
2 also contains distort
ed MoO
6 octah
edra. How
ev
er,th
es
e sol
ely
edg
e-shar
e with octah
edral h
exaoxoiodat
e(VII), IO
65-, anions to form zigzagging on
e-dim
ensional,
e/
journals/inoca
j/41/i10/
eqn/ic0112746
e10001.gif">[(MoO
2)(IO
6)]
3-, chains that ar
e polar. Th
es
e chains ar
e s
eparat
ed from on
e anoth
er by Ba
2+ cations that ar
ecoordinat
ed by additional wat
er mol
ecul
es. Bond val
enc
e sums for th
e iodin
e atoms in
1 and
2 ar
e 5.01 and 7.03,r
esp
ectiv
ely. Crystallographic data:
1, monoclinic, spac
e group
C2/
c,
a = 13.584(1) Å,
b = 7.3977(7) Å,
c =20.736(2) Å,
es/gifchars/b
eta2.gif" BORDER=0 ALIGN="middl
e"> = 108.244(2)
es/
entiti
es/d
eg.gif">,
Z = 4;
2, orthorhombic, spac
e group
Fdd2,
a = 13.356(7) Å,
b = 45.54(2) Å,
c = 4.867(3) Å,
Z = 8.