I-Pb (Iodine-Lead)

  • PDF / 176,520 Bytes
  • 2 Pages / 593.972 x 792 pts Page_size
  • 59 Downloads / 212 Views

DOWNLOAD

REPORT


ection III: Supplemental Literature Review

I-Pb (Iodine-Lead) H. Okamoto

The Pb-I phase diagram was unknown in [Massalski2], which was published in 1990. Since then, [1995Kon] determined the phase diagram in the region between Pb and PbI2 by differential thermal calorimetry. Figure 1 shows the Pb-I phase diagram of [1995Kon] revised by [2006Zhu]. A minor modification was made by this editor to avoid phase rule violation. In the phase diagram of [2006Zhu], PbI2 was shown to have a homogeneity range expanding to the I-rich side as the temperature increases. The syntectic melting reaction of

Table 1 Phase

PbI2 was shown as a congruent type in the phase diagram of [1995Kon]. Figure 1 may need confirmation because the L1 + L2 miscibility gap is very close to the edge of the phase diagram, which is unlikely [1991Oka]. The syntectic melting of PbI2 is also subject to further investigation because the syntectic reaction is unlikely to occur in binary systems unless the composition of the compound is very close to either side of the liquidus at the syntectic temperature [1993Oka]. Table 1 shows Pb-I crystal structure data.

Pb-I crystal structure data Composition, at.% I

Pearson symbol

Space group

Strukturbericht designation

Prototype

0 66.7

cF4 hP6

 Fm3m P3m1

A1 ...

Cu ...

(Pb) PbI2

Weight Percent Iodine 0

10

20

30

40

50

60

70

80

90

100

450

L3

L2

406°C

Temperature, °C

400

L1 368°C

350

327.502°C

PbI2

300

250 0

Pb Fig. 1

320

10

20

30

40

50

60

70

80

Atomic Percent Iodine

Pb-I phase diagram

Journal of Phase Equilibria and Diffusion Vol. 31 No. 3 2010

90

100

I

Supplemental Literature Review: Section III References 1991Oka: H. Okamoto and T.B. Massalski, Thermodynamically Improbable Phase Diagrams, J. Phase Equilib., 1991, 12(2), p 148-168 1993Oka: H. Okamoto and T.B. Massalski, Guidelines for Binary Phase Diagram Assessment, J. Phase Equilib., 1993, 14(3), p 316-335

1995Kon: R.J.M. Konings, A. Kok-Scheele, and E.H.P. Cordfunke, On the Phase Diagrams of the Systems Pb-PbI2, PbI2-NaI and PbI2-ZnI2, Thermochim. Acta, 1995, 261, p 221-225 2006Zhu: X.H. Zhu, B.J. Zhao, S.F. Zhu, Y.R. Jin, Z.Y. He, J.J. Zhan, and U. Huang, Synthesis and Characterization of PbI2 Polycrystals, Cryst. Res. Technol., 2006, 41(3), p 239-242

Journal of Phase Equilibria and Diffusion Vol. 31 No. 3 2010

321