The radial distribution curves for As
2(Se
1-xTe
x)
3 were obtained and the atomic structure and the co-ordination number was investigated on the vitreous state and on the crystallization process at 150°C.
In the vitreous state for a composition range
X=1/2_??_4/5, the radial distribution curves showed peaks at the following atomic distances.
the first peak γ
1=2.60±0.05Å
the second peak γ
2=3.95±0.05Å
the third peak (shoulder) γ
3=5.0_??_5.3Å
These values were independent of the cooling conditions in the sample preparation and manifested no change on crystallization.
The mean number of the nearest-neighbour anion atoms surrounding the As atom, as estimated from the area under the first peak, changed remarkably from 3.40±0.2 in the vitreous state to 3.8±0.2 after 4 hr, 4.0±0.2 after 8 hr, 4.4±0.2 after 10 hr on crystallization at 150°C.
The value 4.4±0.2 was equal to the mean co-ordination number of the Te atoms surrounding the As atoms in crystalline As
2Te
3.
View full abstract