1070-4272/02/7501-0159$27.00C2002 MAIK [Nauka/Interperiodica]
Russian Journal of Applied Chemistry, Vol. 75, No. 1, 2002, pp. 159!161. Translated from Zhurnal Prikladnoi Khimii, Vol. 75, No. 1,
2002, pp. 159!161.
Original Russian Text Copyright + 2002 by Baev.
Thermolysis of Dimethyltellurium and Its Mixture
A. K. Baev
Belarussian State Technological University, Minsk, Belarus
Received September 19, 2000; in final form, October 2001
Abstract-Thermolysis of dimethyltellurium and its mixture with dimethylcadmium (1:1) was studied.
The composition of the thermolysis products was determined. The thermolysis mechanism was proposed.
The kinetic data on thermolysis of organometallic
compounds are used to optimize the conditions of
production of semiconductors and their low-tempera-
ture doping. However, the thermolysis mechanisms of
practically important organometallic compounds and
especially of binary mixtures  are studied insuf-
In this work we studied thermolysis of dimethyl-
tellurium and its mixture with dimethylcadmium.
Thermal degradation of Te(CH
to metallic tel-
lurium at 6233773 K under static conditions was
examined in . The content of the main gaseous
, decreases with increasing temperature.
The process involves intramolecular disproportiona-
tion of CH
groups with intermediate formation of
organotellurium polymer which degrades further to
) 6 nCH
6 nTe + n/2CH
+ n/2C. (2)
In the condensed product CH
and CH groups were
detected. The carbon content in metallic tellurium
was 2.5%. Yablokov et al. studied thermolysis of
under static conditions . The following
temperature dependence of the rate constant was
lnk = (28.0+ 2.5) 3 (43 200+ 3100)/RT.
In preliminary experiments the process was per-
formed to a constant pressure in the system (~20 h). It
was found that the degree of thermolysis at tempera-
tures higher than 610 K is almost independent of tem-
perature. The ratio of the attained constant pressure
and the initial pressure p
at 603, 606, 617,
622, 633, and 641 K is 1.49, 1.50, 1.31, 1.33, 1.30,
and 1.35, respectively.
Needle crystals and a translucent dark brown film
were formed on the walls of the gage chamber. This
agrees with data of Galliulina et al.  and indicates
gas-phase thermolysis of the sample with subsequent
condensation of the products on the walls of the gage
chamber. At t = 0 the a3t kinetic curves (Fig. 1) ob-
tained at the initial Te(CH
concentration of 3.8 0
M intercept different lengths on the ordinate,
which is due to certain decomposition of the initial
sample in the course of attaining the required tempera-
ture. Therefore, when treating the kinetic curves, we
took as the start of the process the moment at which
the constant temperature was attained. The kinetic
data were approximated by equations of different
orders. Up to the degree of decomposition of 0.830.9
the best fit was obtained with the first-order equation.
The experimental results are described well by the
linear anamorphosis of the kinetic equation. The rate
constants k 0 10
at 559.6, 577.2, 595.2, 603, 613,
Fig. 1. Thermolysis of dimethyltellurium at (1) 548.6,
(2) 559.6, (3) 577.2, and (4) 595.2 K. (a) Degree of sub-
strate decomposition and (t) time.