Überblick über einige physikalisch-chemische Eigenschaften der AIIIBv-Verbindungen unter besonderer Berücksichtigung der Zustandsdiagramme

Folberth, O. G.

doi:10.1007/bfb0119066

Cited by 3 publications

(3 citation statements)

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“…In our own systematic investigations of the vapor deposition of elementary boron (5) however, we have shown that it is impossible to prepare this so-called "I-tetragonal boron" B4sBz in a pure form and that it can therefore no longer be considered a true polymorph of elementary boron. We suggest that the formation of this boron "modification" in the reported experiments (2)(3)(4) was induced in such a way that the deposited boron picked up some carbon from the substrate and reacted on the surface. This resulted in the nucleation and growth of crystals, which actually were tetragonal boron carbide and not pure tetragonal boron.…”

Section: Discussionmentioning

confidence: 70%

“…(9), or reaction [1] only (Ref. 10), was resolved by Stevenson and Yost (11), who calculated the equilibrium constant Kp' of reaction [2] from spectroscopic data and showed that reaction [2] does indeed not contribute in a measurable way to the vapor pressure at T < 1500~ Utilizing the data of Ref. (10), a fairly constant value of ~H~ for reaction [1] was obtained from K r at various temperatures, while the same test of consistency fails for the data of Ref.…”

Section: K;mentioning

confidence: 99%

“…For a summary of the earlier literature on the properties of InP we refer the reader to the review articles of Folberth (2) and Renner (3). Various techniques for growing InP single crystals have been evaluated by Weisberg et al and by Richman (4), who considered the gradient-freeze method as the most suitable technique, since it provides optimum control of the thermal decomposition equilibrium of InP during the process of crystal growth.…”

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confidence: 99%

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Phase Equilibria and Vapor Pressures of Pure Phosphorus and of the Indium/Phosphorus System and Their Implications Regarding Crystal Growth of InP

Bachmann¹,

Buehler²

1974

J. Electrochem. Soc.

110

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The vapor pressure as a function of temperature of several commercial grades of red phosphorus and a specially prepared crystalline sample has been measured. For crystalline red P we obtain a heat of sublimation, δHs=31.9±1 normalkcal/normalmole . The commercial grades yield vapor pressures, which above 450°C are described by the equation In p=−false(10.8±0.4false)×103/T+false(16.5±0.6false) . The sublimation equilibrium of red P can be utilized for controlling phosphorus pressures, p>10 normalatm , with a reproducibility of 10% if commercial P of at least 5N purity is used. Measurements of the pVT relation of phosphorus vapor in the regimes 800°K≤T≤1400°K and 3 normalatm≤p≤35 normalatm reveal deviations up to 10% from ideal gas behavior. Excellent accuracy in describing the behavior of phosphorus vapor is obtained when van der Waals equation is used in conjunction with the critical data of Marckwald and Helmholz and a critical coefficient of 0.375 for calculation of both the co‐volume and the interaction parameter. Consideration of the pressure dependence of the equilibrium constant Kp for the reaction P4=2P2 yielded approximate values for the fugacity constant at 1000° and 1100°C. The pTx relation at the liquidus in the vicinity of stoichiometric InP for indium‐rich and phosphorus‐rich compositions were established by simultaneous vapor pressure and DTA measurements. The melting point of stoichiometric InP is 1335°±1°K and the corresponding equilibrium phosphorus pressure is 27.5±1 normalatm . T−x liquidus data calculated with the assumption of ideal behavior of the liquid are in good agreement with our experimental data. Interpretation of the liquidus pressure data yields values of the standard enthalpies and entropies at 298° K normalΔH°298=22.1 normalkcal/normalmole,normalΔS°298=15.78 normale.normalu. for the reaction normalInP)(normalsfalse)=normalIn)(normals+1/4 P4)(normalg and normalΔH°298=36.0 normalkcal/normalmole,normalΔS°298=25.28 normale.normalu. for the reaction normalInP)(normalsfalse)=normalIn)(normals+1/2 P2)(normalg These results are in excellent accord with the standard enthalpies reported by Panish and Arthur and agree within 3% with literature data on the standard entropies of the reactants. The growth of n‐ and p‐type InP crystals via the gradient freeze technique is discussed and the degree of control of the liquidus concentration is evaluated for various conditions of crystal growth.

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Section: Discussionmentioning

confidence: 70%