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Greenwood N.N., Earnshaw A. (eds.) Chemistry of the elements (2ed., Elsevier, 1997)(ISBN 1591242916)(T)(1359s).djvu |
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the metal centre in an unusually high apparent
formal oxidation state, e.g...
In those days, over a century ago, electric vehicles
were popular and sold well compared with the then noisy, inconvenient and rather unreliable petrol-engined vehicles...
§15.2.1
Sulfides of the metallic elements
679
By contrast with the water-soluble sulfides
of Groups 1 and 2, the corresponding heavy
metal sulfides of Groups 11 and 12 are amongst
the least-soluble compounds known...
coordination, features a square-planar array of
4 S atoms about each Pt, thus emphasizing its
covalent rather than ionic bonding...
Its smell is noticeable at
0.02 ppm but the gas tends to anaesthetize the
olefactory senses and the intensity of the smell
is therefore a dangerously unreliable guide to
its concentration...
In particular it is useful for
converting ketonic and aldehyde >C=O groups
to >CF2, and carboxylic acid groups -COOH to
-CF3...
It oxidizes KI (and I3~) in
acetone solution to give iodine (note SF4 converts
acetone to Me2CF2)...
However, it can be stabilized by the presence
of as little as 0.01% PCI5 and can be purified
by distillation at atmospheric pressure in the
presence of 0.1% PC15.(I44) The sulfur dichloride
molecule is nonlinear (C2,,,) as expected, with
S-Cl 201 pm and angle Cl-S-Cl 103°...
The first eight members with n = 1 — 8 have
been isolated as pure compounds, and mixtures
up to perhaps S100CI2 are known.' Specific
compounds have been made by F...
SBr2
probably does not exist at room temperature but
has been claimed as a matrix-isolated product
when a mixture of S2Cl2/SCl2.Br2:Ar in the ratio
1:1:150 is passed through an 80-W microwave
discharge and the product condensed on a Csl
148 G...
a and features an S7 ring with
alternating S-S distances and a pendant iodine
atom; the conformation of the ring is the same as
in S7, S8, and SgO (p...
Thionyl chloride begins to decompose
above its bp G6°) into S2C12, SO2, and Cl2;
it is therefore much used as an oxidizing
and chlorinating agent in organic chemistry...
Similar oxidation of cyclo-Sj, and a-
and /3-S6 in CH2CI2 solution yields crystalline
S7O, S7O2, and a- and ?-S6O...
More recently it has
been shown that, whereas neither SO2 nor
OSMe2 (dmso) react with first-row transition
metals, the mixed solvent smoothly effects
dissolution of the metals with simultaneous
oxidation of SIV to SVI, thereby enabling the
production of crystalline solvated metal disul-
fates (S2O72") in high yield.A81) Examples
are: colourless [TiIV(OSMe2N][S2O7]2, green
[Vni(OSMe2N]2[S2O7]3 and the salts
tMn(OSMe2N]tS2O7], where M = Mn (yellow),
Fe (pale green), Co (pale pink), Ni (green), Cu
(pale blue), Zn (white) and Cd (white)...
/ran.T-lPtClPh(PEt3J] +SO2]
DcoordinatePt)
[PtCIPh(PEt3J(SQ2)l E-coordinate)
rram-[PtCI(PEt3J (S(OJPh)] D-coordinate)
Intermolecular insertion of SO2 can also occur
(without prior formation of an isolable complex)
and the general reaction can be represented by
the equation:"831
182 G...
It
can be obtained on a laboratory scale by the
double distillation of oleum in an evacuated all-
glass apparatus; a small amount of KMnO4 is
sometimes used to oxidize any traces of SO2...
Monomeric neutral SO4 can be obtained by
reaction of SO3 and atomic oxygen; photolysis of
SO3/ozone mixtures also yields monomeric SO4,
which can be isolated by inert-gas matrix tech-
techniques at low temperatures A5-78 K)...
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