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Durch Fourier-Synthese wurde die Kristallstruktur der Verbindung LiGaGe verfeinert. Sie kristallisiert in der RG 186 (P63mc–C) mit geordneter Verteilung der Ga- und Ge-Atome auf die Punktlagen des Wurtzit-Gitters, die Li-Atome besetzen die Oktaederlucken dieses Gitters. Das Existenzgebiet der hexagonalen Verbindung LiGaGe wurde durch rontgenographische Phasenanalyse abgegrenzt; in einem Teilbereich des Systems LiGaGe wurden dabei weitere Phasen unterschiedlicher Zusammensetzung gefunden, die kubisch-flachenzentriert kristallisieren und z. T. ein groses Homogenitatsgebiet besitzen. Ternary Phases in the System Lithium—Gallium—Germanium The crystal structure of the ternary compound LiGaGe was refined by Fourier synthesis. The space-group of the structure is Nr. 186 (P63mc–C), and the Ga and Ge atoms form a Wurtzite lattice, the octahedral sites of which are occupied by the Li atoms. The homogeneity range of the compound LiGaGe was investigated, several further ternary phases with a cubic-fc. lattice could be found in the LiGaGe system.

A subsolidus phase study of the K2O-Nb2O5-WO3 system was made. A ternary compound K2ONb2O52WO3 of the pyrochlore structure was found. The existence of a tungsten-bronze type solid solution phase was revealed. The range of this phase spreads from 34–57–9 to 20–50–30. X-ray, optical and dielectric properties were examined. The composition K6W4Nb6O30, previously reported by one of the authors, was proved not to exist as a single phase.

Reflectivity spectra of the chalcopyrite ternary compound ZnGe${\mathrm{P}}_{2}$ are studied experimentally and theoretically. The measurements of the reflectivity in both the complete parallel and perpendicular polarizations are made at 5\ifmmode^\circ\else\textdegree\fi{}K. A full zone energy-band structure, the reflectivity and imaginary part of the frequency-dependent dielectric function are calculated using the empirical pseudopotential method. Comparison is made with the measured reflectivity and modulated reflectivity and prominent features in the experimental spectra are identified and associated with interband transitions. In addition, spin-orbit interactions are included at a few points of the Brillouin zone.

>The composition range and free energy of formation of UMoC/sub 2/ were studied. Results show that the compound UMoC/sub 2/ is the only low-temperature equilibrium ternary compound in the U -- Mo- C system and that this compound shows non-stoichiometric behavior at temperatures above 1400 deg C. This probab1y extends to its melting point. (JRD)

The Tl 2 S /1b Sb 2 S 3 phase diagram was examined and three ternary compounds, Tl 3 SbS 3 , TlSbS 2 and TlSb 5 S 8 were found. The electrical and photoelectrical properties of TlSbS 2 crystals and evaporated thin films were investigated.

Phase equilibria in the system BaO-SrO-SiO2 in air were established using conventional solid-state techniques. The phase relations in the boundary system SrO-SiO2 were completed by determining the liquidus temperatures for the SrO-rich portion of the diagram. The known compounds, SrSiO3, Sr2SiO4, and Sr3SiO3, melted congruently at 1580°±15°, 2325°±15°, and 2170°±15°C, respectively. Simple binary eutectics exist between (1) Sr2SiO4 and Sr3SiO5 at 2150°±15°C and ∼27 mol% SiO2 and (2) Sr3SiO5, and SrO at 2080°±15°C and ∼23 mol% SiO2. All Alkemade lines were established for the ternary system; two of these joins were examined in detail because of extensive solid-solution regions. On the Ba2SiO4-Sr2SiO4 join, a maximum solubility of ∼70 mol% Sr2SiO4 in Ba2SiO4 appears to exist at 2100°±15°C, the eutectic reaction temperature. A two-phase region apparently connects the eutectic reaction isotherm with a high-temperature polymorphic transition (α′±α) of Sr2SiO4. Below this transition temperature, a complete solid-solution series exists between Ba2SiO4 and α′-Sr2SiO4. The BaSiO3-SrSiO3, join contains limited solid-solution regions at the extremities which arise from the solid solubility of 40 mol% SrSiO3 in the high-temperature (β) polymorph of BaSiOs3 and 20 mol% BaSiO3 in SrSiO3 at 1210°±15°C. The only ternary compound isolated, BaSrSi3O8, has a lower limit of stability at 1220°±3°C and melts incongruently at 1275°±3°C.

A ternary compound UNCl has been prepared by the reaction of uranium chlorides with aluminium or silicon and nitrogen. The chemical composition of UNCl has been determined by chemical analyses. The crystal structure of UNCl has been determined by X-ray analysis. From the relative line intensities of X-ray diffraction of UNCl, Patterson function was calculated by means of the computer code UNICS. From this calculation, the configuration of atoms in the crystal of UNCl has been deduced.

The system In Bi-Bi-Sn has been investigated by thermal analysis, metallographic, and X-ray procedures. No ternary compound was encountered, and a ternary eutectic composed of a Sn-rich solid solution, Bi, and InBi occurs at 77.5 ± 0.5° C. It contains 18 wt % Sn, 12% Bi, and 70% InBi. The solid solubilities at the Bi and InBi ends of the phase diagram are very restricted, but the Sn-rich solid solution contains 55 wt % Sn, 14% Bi, and 31% InBi at the eutectic temperature.

The 1200°C isothermal section of the system CaO-BaO-WO3 was studied in detail. The system contains one ternary compound, Ba2CaWO6, which can exist in binary equilibrium with BaO, CaO, Ba3WO6, Ba2WO5, BaWO4, and Ca3WO6. The composition range of solid solutions based on the ternary compound extends from Ba2CaWO6 to Ba1.86Ca1.14WO6 at 1200°C. Solid solubility along the binary join BaWO4-CaWO4 was studied in the interval 1000° to 1340°C. Maximum solid solubilities occur at the eutectic temperature (1340°±10°C) and are 18 mol% CaWO4 in BaWO4 and 3.5 mol% BaWO4 in CaWO4. A phase diagram is given for the BaWO4-CaWO4 system. Evidence is presented which shows that Ba2WO5 is a stable phase, and the BaO-WO2 phase diagram is revised accordingly. There are 3 polymorphs of Ba2WO5 related by rapid reversible inversions at 1385°±5° and 1490°±10°C. The low-temperature form of Ba3WO6. is tetragonal (α=8.65(2) A and c=16.43(4) A), not cubic as previously reported. The compounds Ca6WO9, BaW2O7, BaCa2WO6, Ba5CaW2O12, and Ba1.5Ca1.5WO6 reported in earlier studies were not confirmed.

1. The Cr-Re-B system was studied by methods of x-ray structural and microstructural analyses and the isothermal section at 1400°C was constructed. 2. The solubility of the third component in the binary borides of chromium and rhenium is marked only for the lower borides up to 50 at.% Re in Cr2B and about 10 at.% Cr in Re3B). 3. At a composition of Cr3Re2B5, there exists a ternary compound possessing a rhombic structure of the FeB type (a= 5.698–5.749±0.005, b=2.959–2.973±0.003, c=4.261–4.297±0.003 A). 4. In the unheat-treated samples, a ternary compound CrRe3B4−x was observed with a tetragonal structure of theα-MoB type (a=2.997±0.002, c=16.515±0.01 A).

From thermodynamical study, it was inferred that any stable ternary compound in the region U-UC-UO2 will be in equillibrium with CO gas of 10-310-4mmHg at 1, 600°C, if it exists. Mixed powder compact of UO2 and UC having a ratio of 03 to 1 as well as that of UO2 and UC2 of 1/33 to 1 (ratio of UO2 to UC2) were heated at 1, 600°C for 4 hr in vacuum of 10-4mmHg. The phases after the reaction were identified and quantitatively determined by X ray diffractographic techniques, which showed that the amount of UO2 was much decreased and that of a UC-like phase having a slightly smaller parameter than UC was increased. This latter phase was considered to be UC1-xOx, and the x was calculated from the ratios of UO2 to UC1-xOx before and after the reaction. The values of x was also determined by chemical analysis of carbon and nitrogen, which was nearly equal to the value of x from the X ray analysis. The largest value of x was 0.83 and was obtained by the reaction of a compact of UO2 and UC of 3 to 1 ratio. The lattice parameter of this UC1-xOx was measured to be 4.944 A and its theoretical density was calculated to be 13.91.

As a result of an investigation of Ti-V-C alloys, the isothermal section of this system at 1450°C was constructed. The system has three single-phase fields-(Ti, V), (Ti, V)C, and V2C, as well as the corresponding twophase fields (Ti, V) + (Ti, V)C, (Ti, V)C + V2C, and V2C + (Ti, V), and (Ti, V)C + C and the three-phase field (Ti, V)C + (Ti, V) + V2C. No ternary compounds are formed in this system.

X‐ray, optical and electron microscope, and chemical etching techniques have been used to investigate a striated microstructure observed in zone refined single crystals of the AgSbTe2 structure. This microstructure, originally thought to be fine twin lamellas, has been identified as a Widmanstatten precipitate of Sb2Te3 upon the {111} planes of the matrix face‐centered cubic material. In addition, the evidence obtained from all the measurements made on this material indicates that the ternary compound of the AgSbTe2 type does not melt congruently.

Several investigations have now been made of the constitutions of ternary aluminium-rich alloys containing transitional metal solutes. Consideration of the results obtained has led to the conclusion that in aluminium-rich alloys, the transitional metal atoms may accept electrons from the structure as a whole, and that the ternary compounds formed have many of the characteristics of electron compounds. Although the acceptance of electrons may be understood in terms of the completion of the 3 d band of the transitional metal, consideration of the Brillouin zone structures of Co 2 Al 9 , Co 2 Al 5 and NiAl 3 suggests, empirically, that the numbers of electrons accepted per atom are greater than the band theory would indicate, and are more nearly equal to the vacancies in the 'atomic orbitals’ postulated in the Pauling theory of transitional metals. Further information with regard to the alloying characteristics of transitional metals has been sought by investigating ternary alloys of aluminium and silicon with chromium, manganese, iron, cobalt and nickel. The results are discussed in the present paper. Assuming acceptance of electrons by the transitional metals to extents given by the vacancies in the 'atomic orbitals’ postulated by Pauling, it is found that the ternary compound of higher electron: atom ratio in the aluminium-chromium-silicon system has a similar electron concentration to that of the ternary compound of lower electron: atom ratio in the aluminium-manganese-silicon system. This behaviour is repeated for the systems aluminium-manganese-silicon and aluminium-iron-silicon; in this case the compounds involved (α(AlFeSi) and α(AlMnSi)) are isomorphous and form uninterrupted solid solutions with each other. The compound of higher electron: atom ratio in the system aluminium-iron-silicon (β(AlFeSi)) has no counterpart in the aluminium-cobalt-silicon system, but Co 2 Al 9 dissolves silicon until the electron: atom ratio is raised sufficiently to overlap the range of electron: atom ratios characteristic of β(AlFeSi). As the number of vacancies for electrons per atom of transitional metal decreases, the ternary compounds formed tend to move to progressively higher ranges of electron: atom ratio. These results are discussed in relation to previous work, and support the general hypothesis of acceptance of electrons by transitional metals. Of particular significance are the observations that silicon and nickel both dissolve in Co 2 Al 9 until the same maximum electron: atom ratio is reached; that α(AlMnSi) and α(AlFeSi) form uninterrupted solid solutions and, according to the hypothesis, have similar electron:atom ratios; and that structural relationships exist between various compounds whose electron: atom ratios are similar.

Recently, a new refining method, which depends chiefly upon the partial melting of impure aluminium, has been introduced by one of the present writers. (I. Obinata; Jour. Min. Inst. Japan, 53, (1937), 542. Jap. Pat. No 124398) In this method, the vessel containing the molten aluminium is rotated about a vertical axis and cooled down until the primary crystals of. impurities, FeAl3 in particular, are separated from the eutectic mother-liquor by the action of centrifugal forces. In the present paper, aluminiums containing one or more elements, Fe, Si, Ti, Cu, Mg, Zn and Sb as impurities have been subjected for refining under various rates. From the chemical analysis of the results obtained, the follwing conclusions have been drawn; While the elimination of iron and titanium is easy, that of silicon is difficult unless it exists as a ternary compound, FeAl3 FeSi2; If aluminium contains a large amount of magnesium or zinc as impurity, the content of iron in the refined parts can be lowered below 0.8%.

The constitution of copper-rich copper-aluminium-tin alloys has been examined by metallographic and X-ray methods in order to investigate the nature of a suspected ternary phase stable at temperatures below that of the eutectoid decomposition in the copper-ahiminium system. The existence of a ternary phase T has been established, and isothermal diagrams have been established at various temperatures between 650 and 505° C. The characteristic of the ternary phase is a constant copper content of approximately 75 atomic %, which is maintained despite a wide variability in the tin and aluminium contents. At 505° C its structure is body-centred cubic, but at lower temperatures the phase splits up into two phases of different crystal structure (β´ and T). The structure of the low-temperature β' phase formed below a tin content of 6·3 atomic % is ordered body-centred cubic, and the unit cell contains 16 atomic sites. The T phase has a small range of homogeneity in the region of 11 to m13 atomic % of tin, and its crystal structure is very similar to that of the δ phase in the coppertin system. At intermediate compositions β´ and T exist together at the lower temperatures. Accurate density measurements show that the T phase contains vacant atomic sites, which increase in number as the tin content increases. The difference between the low-temperature structures formed from T is to be attributed to this development of defects. The results are discussed with particular reference to the factors affecting the formation of the T phase, and the conditions under which ternary compounds may be expected in alloys of copper and silver with elements of the B subgroups of the periodic table.

Im ternaren System Ni/Be/B wurde eine kubisch kristallisierende LAVES-Phase mit der mittleren Zusammensetzung [Ni0,63Be0,37] [Be1,40B0,60] und einer noch nicht genau abzugrenzenden Phasenbreite gefunden. Die Nickelatome und ein entsprechender Anteil des Berylliums sind auf den A-Platzen, die Ubrigen Berylliumatome und Bor auf den B-Platzen des AB2-Gittertyps jeweils statistisch verteilt. Die Gitterkonstante variierte trotz der Phasenbreite nur zwischen a = 5,762 und 5,772 ± 0,004 A. Eine weitere ternare Verbindung des Systems existiert bei einer mittleren Zusammensetzung Ni6Be7B3. Ihr Gitter konnte noch nicht bestimmt werden. Die bisherigen Anhaltspunkte fur die Existenz einer kubischen LAVES-Phase im System Co/Be wurden bestatigt. Man erhalt sie aus der Schmelze bei einer stochiometrischen Zusammensetzung Co:Be = 1:8 bis 1:12. Im gleichen Bereich des Systems wird bei Temperaturen unterhalb 1150° vorwiegend eine neue hexagonale Phase gebildet. In der kubischen Phase kann Bor auf Be-Platzen substituiert werden, womit eine Gitterkontraktion bis zu 2,5% verbunden ist. Dagegen last die schon bekannte LAVES-Phase Cu Be2 Keine Borsubstitution zu. A compound with the mean composition [Ni0.63Be0.37][Be1.40Be0.60] having the cubic C15 structure of MgCu2 was found in the ternary system Ni/Be/B. The Ni atoms and part of the Be atoms are statiscally distributed on the Mg sites of the MgCu2 lattice, the rest of the Be atoms and the B atoms being on the Cu sites. The lattice constant has values between 5.762 and 5.772 A. Another ternary compound with a still unknown structure has the mean composition Ni6Be7B3. In the Co/Be system the existence of a phase with C15b structure could be established. The compound is formed at a Co:Be ratio of 1:8–1:12 from the molten components. At temperatures below 1150°, a new hexagonal Co/Be phase was observed in the same region of the system. Boron can occupy the Be positions of the cubic Co/Be phase, causing a lattice contraction up to 2.5%. The already known CuBe2 with C15 structure, however, does not allow substitution by boron.

In the introduction, some of the applications of the AIIIBV compounds are indicated. Their limitations are mentioned and two possibilities are suggested for overcoming these. In view of the AIIIBV compounds' outstanding contribution in recent years, the investigation of their isoelectric analogues, the AIIBIVC 2 V compounds, is suggested as a logical step. CdSnAs2 is shown to be the most investigated compound in this group, although several phosphides have potentialities as materials with energy gaps in the visible region of the spectrum. A comprehensive bibliography of the published work on AIIBIVC2/suV compounds is given.

Synopsis The constitution of the aluminium-manganese-zinc alloys was examined, in the range 0–6 per cent, manganese and 0–40 per cent, zinc, by the establishment of a 500° C. isothermal. With increasing zinc, MnAl6, T1, and MnAl4 enter successively into equilibrium with the aluminium-zinc solid solution (α). T1 is a ternary compound analogous to corresponding compounds in the systems aluminium-manganese-nickel and aluminium-manganese-copper. Solidus curves, at constant manganese contents, agree with the results in the solid state. (α+T1 +MnAl6) alloys melt at 542° C. to 545° C., while (α+T1+MmAl4) alloys melt at 508° C. Similar work on aluminium-manganese-cadmium alloys at 600° C. reveals no ternary compound. Thus nickel, copper and zinc are within the zone of favourable atomic size for the formation of ternary compounds of the type considered, while cadmium, with a larger atom, is outside. The formation of growth twins in T1 crystals was observed and is described.

Im System Al/Bc/B wurde eine ternare Verbindung mit der idealisierten Zusammensetzung AlBeB als feinkristalline, dunkle Substanz aufgefunden. Sie kristallisiert im Antifluoritgitter, dessen Metallagen geordnet mit Be- und Al-Atomen besetzt sind. Infolge teilweiser Mischkristallbildung mit Be2B wurde das Verhaltnis Be:Al stets etwas groser als eins und von den Darstellungsbedingungen abhangig gefunden. Dabei schwankte die Gitterkonstante zwischen 4,952 und 4,925 A. Die Dichte, Loslichkeit und der Stabilitatsbereich der Verbindung wurden untersucht. In the system Al/Be/B a ternary compound with the idealised composition AlBeB has been observed as a fine crystalline dark substance. It crystallises with an antifluorite structure, with ordered Be- and Al-atoms in the metal positions. On account of partial formation of mixed crystalls with Be2B, the ratio Be:Al is always greater than one and dependent on the conditions of preparation. The lattice constant varies between 4.952A and 4.925 A. Density, solubility, and the stability of the compound have been examined.

Thermal analysis, metallographic, and X-ray procedures were used to investigate the Sn-Sn4As3-SnTe subsystem of the ternary system tin-arsenic-tellurium. The subsystem is of the simple eutectic type with no ternary compound formation. A binary eutectic valley runs across the diagram from the Sn4As3-SnTe binary eutectic at 576.5°C to a ternary eutectic which is indistinguishable from the Sn4As3-Sn binary eutectic at 231.3°C with 0.5 wt % Sn4As3 and 99.5% Sn. More than 90% of the compositional area is dominated by the primary freezing of an SnTe-rich phase, and an Sn4As3-rich phase is the first to crystallise from the melt over most of the remaining area. Terminal solid solutions are very restricted.

An investigation of the phase constitution of the indium-antimony-tellurium system (excluding the indium and tellurium corners), using X-ray powder- and differential thermal analyses, is described. A survey is made of the data published on both the binary and ternary systems. The results of these analyses are reported: a solubility of 49 at.% tellurium in antimony and of 11 at.% antimony in InTe are deduced, and the consequent modifications of the structures are examined. It is concluded that InTe solid solutions undergo a transition at 57O °C. The process of decomposition at approximately 556 °C of the ternary compound, X, having a small solid-solubility about In 50, Sb 15, Te 35 at.%, is discussed. The ternary eutectic temperatures for the InSb + InTe + X and InSb + InTe + Sb regions are 480 °C and 485 °C, respectively. Initial melting of InTe + In 2 Te 3 + Sb samples occurs at 551 °C at a peritectic point within the In 2 Te 3 + Sb region. A minimum in the binary curve results in a solidus temperature of 542 °C for most of the broad In 2 Te 3 + Sb region.

The mutual solubility of UAl/sub 2/ and UFe/sub 2/ amounts to 19 mole% at 1000 deg C and is accompanied by a change of lattice constants according to the larger radius of Al. A ternary compound U(Fe,Al)/sub 2/ (C14 type) was found in the quasibinary system UAl/sub 2/--UFe/sub 2/, ranging from 33 to 59 mole% UAl/ sub 2/. It may be explained in terms of Laves phases. The relative solubility of the structure types C14, C15, and C36 was studied as a function of electron concentration and some new points of view regarding the stacking sequence are given. (auth) H03 alues for the thermal conductivity obtained in the temperature range from room temperature to 1100 deg F are believed accurate within 5%. (auth)

The reaction mechanisms and the structures of the phases formed during the hot dipping of iron in 0 to 10 pct Al-Zn alloy baths at temperatures of 450° to 700°C were studied by X-ray diffraction and electron microprobe analysis techniques. A new mechanism for the inhibition reaction between iron and zinc is proposed. At bath temperatures below 600°C, a thin layer of an Fe-Al-Zn ternary compound forms on the iron surface and inhibits the growth of Fe-Zn phases. Breakdown of inhibition occurs during the dipping process when the ternary compound becomes rich in aluminum and transforms to a more stable structure which is isomorphous with Fe2Al5. While this breakdown is occurring, the zinc atoms react with iron and form the conventional Fe-Zn phases.

The present paper states the properties of a new ternary compound Cu4SnP10 crystallized in a f.c.c. lattice with parameter a = (10.260 ± 0.002) A. The composition of the compound is verified by chemical, X-ray-phase, and micro-structure analysis. Basic electric and optical properties of the compound are investigated. Die vorliegende Arbeit stellt die Eigenschaften einer neuen ternaren Verbindung Cu4SnP10 fest, die in kubisch flachenzentriertem Gitter mit dem Parameter a = (10,260 ± 0,002) A kristallisiert. Die Zusammensetzung wird durch chemische, rontgenographische und Mikrostrukturanalyse bestatigt. Die grundlegenden elektrischen und optischen Eigenschaften der Verbindung werden untersucht.

1. Using differential thermal and x-ray structural analyses, the binary systems KCl−UO2Cl2 and NaCl−UO2Cl2 have been studied and their melting diagrams constructed. 2. The liquidus surface has been constructed for the NaCl−KCl−UO2Cl2 ternary system and the region of existence of a ternary compound of composition KNa2(UO2)2Cl7 has been found.

The existence of a ternary compound with the stoichiometry of GdTlS2 is reported for the first time. It has trigonal symmetry, with unit cell parameters a = 3.643 and c = 6.81A and with the atomic coordinates Cd(000); Tl(23, 13, 12); SI(13, 23, 14; SII(13, 23, 34), in the space group P3m1. The compound is a typical semiconductor with an energy gap of about 1.5 eV. Under intrinsic conditions, the hole mobility obeys μ∼ T−2.1 and the thermal conductivity H∼ T−1.4. It is supposed that the carriers are mainly scattered by lattice vibrations, with quadruple-phonon processes predominating.

The equilibrium phase diagram for the lithium-, sodium-, thorium-fluoride ternary system was determined experimentally using standard laboratory methods. Crystallization reactions in LiF NaFThF 4 mixtures were found to result in the occurrence of fourteen singular and invariant equilibrium points at the liquidus, including three eutectics at the LiFNaFThF 4 compositions, 30−56·5–13·5−13·5, 43·5−32·5−5−24 and 54·5−13·5−32 mole%, and at the temperatures of 505, 509 and 525°C. Peritectic invariant points were found at temperatures as high as 825°C. The high-temperature modification of a crystalline phase, long assumed to be NaThF 5 , was identified as the hexagonal modification of the compound, 7NaF. 6ThF 4 , space group, P 3 c 1. In this phase lithium was found to exchange for sodium, to a saturation limit where lithium substitutes at approximately two-thirds of the sodium sites. Ternary compound formation was absent in the system. The results of the present study were the basis for a revision of the NaFThF 4 phase diagram.

Equilibrium relationships in this ternary system were determined by the quenching method. The only ternary compound occurring in the system was found to be Ca2ZnSi2O7, which corresponds to the natural mineral hardystonite. It has a congruent melting point (1425°C.) and a large primary-phase field in the center of the system. Primary-phase fields for cristobalite, tridymite, CaSiO3, Ca3Si2O7, Ca2SiO4, ZnO, and Zn2SiO4 were also determined in part or in full. The results of this work have some bearing on the minerals and reactions occurring in lead blastfurnace slags and in glazes containing zinc oxide.

Phase relationships in the system CaONb 2 O 5 TiO 2 have been studied. A Griffin-Telin hot-stage microscope was used for the determination of the liquidus temperatures, because the mixtures of compositions in this system did not form glasses, thus rendering the quench technique inapplicable. The liquidus fields of the following ternary compounds have been outlined, in addition to those of the binary compounds: (a) a compound having the composition 3CaO.Nb 2 O 5 .3TiO 2 , a pyrochlore structure and melting incongruently; its composition has been determined by subsolidus experiments; (b) a compound having a composition 8CaO.7Nb 2 O 5 .6TiO 2 that melted congruently and appeared to be metastable at subsolidus temperatures; its presence has been established from the shape of the liquidus surface; and (c), another ternary compound, having a composition 6CaO.Nb 2 O 5 .3TiO 2 and melting congruently; its existence has also been established from the shape of the liquidus surface. Perovskite (CaO.TiO 2 ) did not form solid solutions with any of the calcium niobates notwithstanding that the compound 4CaO.Nb 2 O 5 and probably those niobates having a still higher lime content, have a perovskite type of structure.

From the investigation of the constitution Al-Cu-Mg alloy system the author found the existence of a ternary compound called “S” to be in equilibrium with Al-solution as reported in a previous paper. The age-hardening of Duralumin and 24 type Super-duralumin was considered to occur in the course of the precipitation of this ternary compound from Al-solid solution. To confirm this consideration, the present investigation has been made on rolled Al alloys containing Cu and Mg, and he confirmed the similar phenomena of ageing observed on cast alloys. Immediately after quenching from 500° the change of dilatation on tempering was measured. The alloy containing Cu only showed a marked expansion from about 210° and subsequent contraction from about 280°. This change of dilatation was considered to be due to the separation of CuAl2. But the alloy containing Cu and Mg showed an expansion and contraction below 100° and the marked change of dilatation from 200° due to the precipitation of CuAl2 was also observed in an alloy containing about 0.5%. However, the alloys containing 1.5% of Mg and 4% of Cu did not show the irregular dilatation due to the precipitation of CuAl2. Therefore, the author has concluded that the expansion and contraction below 100° are due to the precipitation of S-compounds. This phenomenon was not found in the specimens aged for 1 week. The effect of a small content of Si upon the ageing of Al-alloy containing Cu 4% and Mg 1.5% was studied on rolled alloys. Si did not accelerate the age-hardening of quenched alloys, but the alloys containing 0.6-0.8% Si showed considerable hardening when they were tempered at 150° for 10 hours. The effect of Si upon such Al alloys was discussed from the constitutions of Al-Cu-Mg-Si alloy system. The difference of the ageing-phenomenon is due to the fact that the equilibrium relation displace to the Al-CuAl2-Mg2Si-Si from Al-CuAl2-S-Mg2Si. This fact was proved by similar dilatation curve of these quenched alloys as those ones containing Cu only.

An investigation of the system of CaO-ZrO2-SiO2 led to the discovery of the two ternary compounds; Ca3ZrSi2O9 and Ca2ZrSi4O12 and a study of their properties.

Phase relations in that part of the system SiO2-Al2O5-P2O6 below 50 mole % P2O3 were investigated at subsolidus temperatures. The only ternary compositions which crystallized readily were those lying close to binary compounds and no evidence for ternary compound formation was found. Solid solution between silica and aluminum phosphate, expected on the basis of closely similar lattice dimensions and physical properties, was not indicated by X-ray diffraction, refractive index, or electron-beam microprobe results. Above 80% silica and at a temperature of 1400°C, the only crystalline species was cristobalite whereas below 60% silica, only the cristobalite form of AlPO4 was present. Coexistence of these two constituents seemed to be inhibited, possibly because of the strong glass-forming properties of the component oxides.

Thermal analysis, micrographic, and X-ray techniques have been used to investigate the In2Te3-SnTe isopleth of the ternary system In-Te-Sn. The diagram is a simple eutectic type with no ternary compound formation. The eutectic melts at 611 °C and contains 20 wt.% SnTe, 80 wt.% In2Te3. The solid-solubility of SnTe in In2Te3 is less than 0.5%, but the solid-solubility of In2Te3 in SnTe at the eutectic temperature is 20%. At 550 °C the latter solubility is 15%.

The system W-Re-C was studied by the method of x-ray structural analysis. Phase equilibria were established for as-cast alloys and alloys quenched from 2000, 1500, 1000, and 800°C. Rhenium and α-W2C form continuous series of solid solutions. Forthe composition W3Re2C, there exists a ternary compound with a cubic structure which is related to the β-Mn structure (space group P41 3-O7, a=6.859±0.002 A). At temperatures above 2500°C, there exists the ternary carbide (W, Re)C, which has a cubic face-centered NaCl type structure (space group Fm3m-Oh5, a==4.063± 0.001 A). Preliminary data were obtained on the existence of a rhombic low-temperature W2C modification.

BS>Compatible phases in the system Al/sub 2/O/sub 3/-- Li/sub 2/O-- TiO/ sub 2/ at various temperature levels were determined by solidstate reactions for the portion of the ternary system bounded by Li/sub 2/O--Al/sub 2/O/sub 3/, Li/ sub 2/O--TiO/sub 2/, Al/sub 2/O/sub 3/, and TiO/sub / 2>i. The existence of a ternary compound, Li/sub 2/O-- Al/sub 2/O/sub 3/--4TiO/sub 2/, and nine joins was established. The ternary compound has a lower limit of stability at 1090 plus or minus 15 deg C and dissociates and recombines rapidly at 1380 plus or minus 15 deg C. (auth)

By means of microscopic observation as well as thermal, X-ray and magnetic analyses, ' the constitution of the Ni-Cr-C system was investigated, and its equilibrium diagram was determined, as shown in Fig. 4. In this system, there exist 7 phases, each of which is found in binary systems, that is, γ(Ni), α(Cr), G(graphite), e(Cr4C), η(Cr7C3), ζ(Cr3C2) and κ(CrC), and no ternary compound was in existence. The following 5 non-variant reac-tions, occur in this system the last one being inferred merely through the micro-examination:- 1) Melt (M1)_??_α+γ+e (1305°) 2) Melt (M2)+η+e (1315°) 3) Melt (M3)+η_??_γ+ζ (1260°) 4) Melt (M4)_??_γ+G+ζ (1240°) 5) Melt (M5)+κ_??_G+ζ (?)

Thorium and nickel, dissolved in liquid bismuth, were found to interact with each other and with the solvent to form a solid ternary compound of the apparent composition ThNiBi2. This interaction was studied, at 50° intervals, over the temperature range of 550–700°C. At each temperature studied, the joint solubility of thorium and nickel could be expressed as a mole fraction product, Kxp = XThXNi. The variation of Kxp with temperature can be expressed as log Kxp = 1·115−6379/T(°K). The standard free energy of formation of ThNiBi2 was estimated to be −51 kcal/mole at 650°C.

ZnIn2S4 single crystals, grown from the vapor phase by iodine transport, display interesting current‐voltage characteristics at high electric fields. Some crystals under illumination show an n‐type negative‐resistance effect. However, in other crystals which do not show such an effect, current oscillations occur whose frequency is strongly dependent on the applied electric field and the intensity of the light by which the crystal is illuminated. Furthermore at still higher electric fields, a permanent transformation of the crystals takes place; in these new conditions the crystals display an s‐type negative‐resistance effect.

This work is the first part of an investigation of the possibility of using chemical transport reactions as a general method of growing comparatively large single crystals. Only closed systems are discussed. Optically clear (24 mm long) single crystals of the ternary compound Cd4GeS6 have been grown by pulling quartz ampoules in a vertical furnace, with very slow pulling rates (up to 0.1 mm hr ) . Low supersaturation was used to control the nucleation. The mass transport in a flat temperature gradient was stimulated by using ampoules with large diameters to enhance the convection mechanism. The critical undercooling was found to be ΔT = 3°C at 800°C. The transport rate changes exponentially with the supersaturation.

The preparation of single crystals of black monoclinic and red tetragonal ZnP2 from the elements is described. The crystals contain 50 to 100 ppm Si as an impurity. The melting point of monoclinic ZnP2 is 992±1°C and of tetragonal ZnP2 is 985±1°C. Interplanar spacings are presented for both the red and black polymorphs of ZnP2. Two bands have been observed in the near‐bandgap luminescence of tetragonal ZnP2 at low temperatures. Both bands exhibit sharp lines, respectively, near 2.144 and 2.020 eV, due to no‐phonon decay of bound excitons, and contain much fine structure due to associated phonon‐assisted transitions. These spectra are identical with luminescence bands reported by Akopyan et al., but are attributed to recombinations in the ternary compound semiconductor ZnSiP2. Preliminary measurements of the indirect‐type absorption‐edge spectrum at low temperatures indicate that the energy gap of tetragonal ZnP2 is close to 2.220 eV at 4.2°K and ∼2.14 eV at 300°K.

The phase boundaries in the composition range 0–20 wt.% zinc for the YCd3-Zn pseudo-binary section of the yttrium-cadmium-zinc ternary system are presented. The boundaries were determined through differential thermal analysis, metallographic, and X-ray diffraction studies. A ternary compound which decomposes peritectically at 757 °C was found in this composition range. This compound, whose composition was established to be (YCd3)3Zn2 from neutron activation analyses and density measurements, is hexagonal with a = 15.103 ± 4, c = 14.985 ± 6 A .

The system CaO-Ta2O3-SiO2 was studied using a combination of hot-stage microscopy and the quenching technique. Primary crystallization fields were defined for the various calcium silicates, and for the calcium tantalates: CaO·2Ta2O5, CaO·Ta2O5, 2CaO·Ta2O5, and 4CaO·Ta2O5. A congruently melting ternary compound 10CaO·Ta2O5·6SiO2, isostructural with the mineral niocalite, is the only ternary phase in the system. A large twoliquid region extends across the system from the CaO-SiO2 binary to within 1 wt% of the Ta2O3-SiO2 binary but does not cut it, in marked contrast to the analogous CaO-Nb2O5-SiO2 system. Other somewhat unexpected differences were noted between these systems.

Eleven ternary compounds were synthesised, of which nine are new. The seven most ZnS-rich compounds form a series. Each has a primitive hexagonal lattice witha=3.85±0.01 A. Thec-dimension varies from 37.47 A (39 ZnS∶8 In2S3) to 18.63 A (18 ZnS∶8 In2S3) with a periodicity of 3.14 A which can be related to a decrease in the ZnS content. One of the four remaining compounds (12 ZnS∶8 In2S3) is triclinic, but at least two polytypes are present. The more common variety has the parameters:a=3.86 A,b=15.48 A,c=3.54 A,α=90° 16′,β=120° 02′ andγ=89° 47′. The structure of the other polytype and of compounds 17 ZnS:8 In2S3 and 10 ZnS∶8 In2S3 have not been determined. Stoichiometric ZnIn2S4 has a rhombic hexagonal lattice (a=3.86 A,c=36.95 A). This ternary compound which has been synthesised previously is the only one to show appreciable solid solution. Approximately 2 mole % ZnS is soluble in ZnIn2S4 at 600° C; this increases to 8 mole % at 1080° C.