INVESTICATION OF THE LOWER OXIDE OF SILICON S1O

• Document Type: CREST
• Collection: General CIA Records
• Document Number (FOIA) /ESDN (CREST): CIA-RDP80-00809A000600350460-2
• Release Decision: RIPPUB
• Original Classification: C
• Document Page Count: 3
• Document Creation Date: December 22, 2016
• Document Release Date: August 22, 2011
• Sequence Number: 460
• Publication Date: October 20, 1950
• Content Type: REPORT

Sanitized Copy Approved for Release 2011/09/14 :CIA-RDP80-00809A000600350460-2
1
CLASSIFICATION CONFIDENTIAL
CENTRAL INTELLIGENCE AGENCY REPORT
INFORMATION FROM
FOREIGN DOCUMENTS OR RADIO BROADCASTS CD NO.
COUNTRY USSR
SUBJECT
HOW
PUBLISHED
WHERE
PUBL~iSHED
DATE
PUBLISHED
LANGUAGE
Scientific - Chemistry, silicon oxide
DATE OF .
INFORMATION 1950
DATE DIST. ~ Oct 1950
Thrice-monthly periodical
Moscow NO. OF PAGES 3
THIS OOCUYCN7 CONTAINS IN TORY ATION ARF[DTINO iNE NATIONAL OCi[N St
V' SiNt., JI AND liT AS AY[NTO [D. TITS TRANSYa3510N ORITN[ RCYLL TION
NIB ITL DD CT TLAN~ I R[RRODU CTION Ol i111! TORN OIII RRO NI [IT[D, IS RPO?
suNrLtmtNl IV
REPORT N0.
SOURCE Doklady Akademii Nauk SSSR, Vol LXXII, No 4, pp 699-701, 1950?
INVESTIGATION OF THE LOWER OXIDE OF SILICON Si0
M. S. Beletskiy and M. B. Rapoport
Presented by Acad D. S. Belyankin, 6 Apr 1950
~he importance of the lower volatile oxide of silicon, SiO, in
electrothermic metallurgical processes is mentioned in the text aP
the article. Potential applications of results obtained in the study
of this compound are (1) condensation of silicon monoxide and (2) sub-
sequent oxidation to silicon dioxideq~rss a method of d~poaiting a re-
fractory coating or of hardening and waterproofing a surface under treat-
ment. A table is appended_7
', s
Sanitized Copy Approved for Release 2011/09/14 :CIA-RDP80-00809A000600350460-2
Considerable interest has been devoted in recent years to studying the role
of Si0 in the reduction of silicon dioxide, Gaseous Si0 is foamed as an inter- ?
mediate substance in a number of production processes including: ferroalloys,
silicon, steel products (1), and refractories {2) as well as in silicothermic pro-
cesses. Moreover, the importance of Si0 is well established in the electrothermic
process for producing aluminum-silicon alloys from natural aluminosilicates (3),
where, due to its comparatively high volatility, Si0 exerts and appreciable influ-
ence on the final composition of the alloy, altering the ratio of the two elements
in the alloy in 'favor of aluminum in spite of the letter's relatively higher vapor
tension. Industrial exper.. nce shows that in single-;?and'..triple-phase furnaces,
2.5~, and 7?6y6 of aluminum and x.596 and 22.596 of silicon, r~3pectively are lost `.hrough
evaporation.
The dae^lopm;:nt of electrothermic procedures and other high temperature pro-
cesaes in e*hich Si02 is reduced, as well as several physicochemical and physical
investigatfo~hs, have dispelled former doubts concerning the formation of Si0 in
the gaseous state in tht purse of these processes. Examination of the molecular
spectrum of this compound has bean conclusive proof (4) of that:"
However, no conclusive answer has been given as yet to the problem of whether
Si0 occurs in the solid state or.~~n condensed form prior to decomposing according
to the following scheme: 2510 =-~.S102-}- Si, thus Porming an . equimolecular mixture.
CQ.YI`IDEI~TIA~
r DISTTRIBU~TION
--I I
 Sanitized Copy Approved for Release 2011/09/14 :CIA-RDP80-00809A000600350460-2
Attempts.to prove the presence of Si0 in the solid state have, in'the majority
formed haveeoftensprovenfthemato bevhighlytdispersed mixturessofssiliconadioxide
and silicon.
A considerable step forward along this line was the Work done by P. V. Geld
(5). He produced Si0 by artifical meyns in vscuum, measured its vapor tension
by the molecular discharge method, a+.udied several properties of this compound,
and determined its thermodynamic characteristics But in spite of this, up to
definite proof ofsthe presencetof thisi~ompound inttheisolidnstate),chavennotve
been reliably determined.
. Two attempts have been previously made st X-ray analysis of SiO. Investigat-
ing specimens in which he assumed the presence of 510, Baumann (6) established,on
the basis of their interplanar distances, that the specimens consisted of mixtures
oP silicon and cristobalite, and in some cases silicon carbide. Inuzuka has re-
ported (7) that a Si0 preparation which he investigated had a cubical crystal lat-
tice with the constant s equals 6.4 A. The b~sic cell contained 8 Si0 molecules,
and the spatial group belonged to the group Th.
Beletskiy and Rapoport made X-rsy snalyses of white formations obtained from
the condensation zone of "charge vapors" of sn industrial furnace for fusing silicon
onewhichythecintensiveainterferenceelinesrwereavisible. hAdcorrection wasbmaderPord
X-ray absorption by the specimens.
The results of these analyses are give in the appended table. They indicate
the presence of a mixture of substances with average values of their a equal to
5.41 A and s2 equal to 4.34 A. Substances having such constants would~e silicon
and silicon carbide.
Be assuming that the white substance was a single compound, this substance
by X-ray study was found to have a cubical crystal lattice constant a equals 6.36
A, this Figure conforming closely to Inuzuka's. By recalculating Baumann's values
for the interplanar distances on the bssis of the moat intensive lines, Beletskiy
and Rapoport, with the aid of their own indexes Prom the appended table, determined
the average value Por the crystal lattice constant ea equal to 6.35 A; this Figure
satisfactorily conformed to Inuzuka's data a.a well as to the data cited above.
From these Pi ps Beletaki and Rapoport concluded that Inuzuka investigated
gur . , Y
a compound which was not S10, but rather a mixture of S1 :wd SiC; in other wor.:e,
approximately the same mixture which was studied by Baumann.
Completely different results were ebtained by the Soviet authors in the+ inves-
tigation of preparations obtained as a result of the reduction oP Si02 by ca; bon or
silicon at 1,800? or higher in vacuum, or on the reduction of a mixture of Si0? and
p1203 under the same conditions. Several of the properties oP the resulting compound
were shown to be very similar to those described by Geld. Beletskiy? and Rapoport's
preparation was a yellowish-brown condensate, and Isotropic substance with a refrac-
tion index, determined by 0. I. Arakelyan, of 1.,92-1.94. Its density, established
with a pycnometer, was rho equals 2.13. By X-ray investigation, its cubical crystal
lattice constant was Pound to be a equals 5.16 A. No other type oY interference
being observed on the X-ray picture, it was assumed that this compound was obtained
in a pure state.
Haeed on the figure 2.13 Por the density, Beletskiy and Rapoport calculated
that with Pour molecules in the basic cell the molecular kei~tvt bf; the. cGmpound,.i9,.,.?-
44.3, which is very close to the +.heoretical value Por. 510+
The crystal lattice constant determined by Beletskiy and Rapoport is a speeiPie
,.~. ~ i ".i.c
characteaistic of S10 is the solid state:
caHFO~~~T~~~
Sanitized Copy Approved for Release 2011/09/14 :CIA-RDP80-00809A000600350460-2
 Sanitized Copy Approved for Release 2011/09/14 :CIA-RDP80-00809A000600350460-2
I
CONI:IDE~IT~A~
BIBLIOGRAPHY
1. Geld, A. I. Kholodov, and N. N. Buynov, Doklady Akademii Nauk SSR, LXX,
4, 195'x: '
2. C. A. Zapffe, journal Am Cersm Soc., XXVII{ 10, 293, 1946?
Rapoport, Tsvetnyye metally, 2, 50, 1946.
4. R. Pirs and A. Gayden, Identification oY Molecular Spectra, 1949?
5. Geld and M. N. Kochnev, Zhurnal Prikladnoy Khimii, XXI, 12, 1249, 1948.
6. H. Baumann, Trans. Electrochem. Soc., L}C70C, 95, 1941.
H. Inuzuka, Chem Abstr., }IXXVI, 4001, 1942.
~ppended table follows,]
No of Sin-
S ecp imen Intensit~r 2r delta hKl a2 a2 ~1 a2
1 Average
2 Strong
3 ~~
4 Weak
5 Strong
6 ~~
7'' Very weak
8 ~~ ~~
9 Average
10 "
37.02
0.096
111
29.15
--
200
40.05
46.21
0.149
200
--
18.79
211
40.35
61.55
0.256
202
29.16
--
311
40.10
73.18
0.351
113
29.26
--
--
-~?
78.48
0.395
(110)
2
--
18.89
410
40.14
95.49
0.544
113
--
18.86
(211)2
41.20
102.51
0.605
133
29.30
--
--
--
106.20
0.636
(120)
2
29.30
--
115
40.76
122.03
0.765
(112)
2
29`.33
--
522
40.35
135.97
0.858
115
29.34
--
611
41.28
CONI'IDEN T ~A~
unitized Copy Approved for Release 2011/09/14 :CIA-RDP80-00809A000600350460-2