R. Cadenas et al., T(Z) DIAGRAM AND OPTICAL-ENERGY GAP VALUES OF (AGIN)(2(1-Z))(CDIN2)(Z)TE-4 ALLOYS, Physica status solidi. a, Applied research, 144(2), 1994, pp. 311-316
The T(z) diagram of the system (AgIn)(2(1-z))(CdIn2)(z)Te-4 is obtaine
d from X-ray diffraction and differential thermal analysis measurement
s. At higher temperatures, there is a single phase solid solution acro
ss the complete diagram, the phase changing from a disordered defect z
incblende to a partially- disordered tetragonal symmetry in the vicini
ty of z = 0.9. This high-temperature phase shows a eutectoid reaction
at z = 0.65 and T = 490 degrees C giving the two tetragonal terminal p
hases alpha, with space group I $($) over bar$$ 42d corresponding to A
gInTe2, and gamma, with I4 $($) over bar$$ corresponding to CdIn2Te4.
At lower temperatures, the fields alpha and gamma are separated by a r
elatively wide two-phase field (alpha + gamma) which extends over the
range 0.53 < z < 0.94. Values of room temperature optical energy gap E
(0) are determined from optical absorption measurements in the ranges
of single phase behaviour and the form of the E(0) versus z data curve
is discussed. The form of this T(z) diagram is compared with that of
related systems in which the terminal compounds have similar structure
but differ in space group.