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Showing papers on "Ternary operation published in 2000"


Journal ArticleDOI
TL;DR: In this paper, three empirical rules for the achievement of high amorphous-forming ability (AFA) were calculated with thermodynamical functions for the gross number of 6450 alloys in 351 ternary ammorphous systems.
Abstract: Chemical mixing enthalpy (ΔH chem ) and mismatch entropy normalized by Boltzmann constant (S σ /k B ) corresponding to the three empirical rules for the achievement of high amorphous-forming ability (AFA) were calculated with thermodynamical functions for the gross number of 6450 alloys in 351 ternary amorphous systems. The temary amorphous alloys have ΔH chem of -86 to 25 kJ/mol and S σ /k B of 1.0 × 10 -3 to 5.7. The average values of ΔH chem and S σ /k B are calculated to be -33 kJ/mol and 0.33, respectively. The 30 alloys in 9 ternary amorphous systems including 10 alloys in Ag-Cu-Fe system have positive values of ΔH chem . Most of the ternary amorphous alloys have the values of ΔH chem and S σ /k B inside a trapezoid regicn in ΔH chem - log(S σ /k B ) chart except mainly for the H- and the C-containing alloys. Si-W-Zr system and the 32 alloys having positive values of ΔH chem . The analysis of AFA was carried out for typical five ternary amorphous systems. The following four results are derived. 1) Al-La-Ni and B-Fe-Zr alloys have high AFA in accordance with the concept of the three empirical rules. 2) The further multiplication of alloy components causes an increase in the AFA of Al-B-Fe alloys. 3) Thermodynamical factors represented by melting temperature and viscosity at the melting temperature are required for evaluation of AFA for Mg- and Pd-based amorphous alloys. 4) A tendency for log(S σ /k B ) to increase with decreasing ΔH chem is recognized in each alloys system, implying the stabilization of an amorphous phase against solid solution and intermediate phase.

644 citations


Journal ArticleDOI
TL;DR: In this paper, phase diagram data in the Sn-Ag-Cu system were measured and the location of the ternary eutectic involving L, (Sn), Ag3Sn and Cu6Sn5 phases was confirmed to be at a composition of 3.5 wt.% Ag, 0.91 wt% Cu at a temperature of 216.2±0.3°C.
Abstract: Sn-rich alloys in the Sn-Ag-Cu system are being studied for their potential as Pb-free solders. Thus, the location of the ternary eutectic involving L, (Sn), Ag3Sn and Cu6Sn5 phases is of critical interest. Phase diagram data in the Sn-rich corner of the Sn-Ag-Cu system are measured. The ternary eutectic is confirmed to be at a composition of 3.5 wt.% Ag, 0.9 wt.% Cu at a temperature of 217.2±0.2°C (2σ). A thermodynamic calculation of the Sn-rich part of the diagram from the three constituent binary systems and the available ternary data using the CALPHAD method is conducted. The best fit to the experimental data is 3.66 wt.% Ag and 0.91 wt.% Cu at a temperature of 216.3°C. Using the thermodynamic description to obtain the enthalpy- temperature relation, the DTA signal is simulated and used to explain the difficulty of liquidus measurements in these alloys.

530 citations


Journal ArticleDOI
TL;DR: In this paper, a Caughey-Thomas-like mobility model with temperature and composition dependent coefficients is used to describe the dependence of electron and hole mobilities on temperature, doping concentration, and alloy composition.
Abstract: A Caughey–Thomas-like mobility model with temperature and composition dependent coefficients is used in this work to describe the dependence of electron and hole mobilities on temperature, doping concentration, and alloy composition. Appropriate parameter sets are given for a large number of III–V binary and ternary compounds, including: GaAs, InP, InAs, AlAs, GaP, Al0.3Ga0.7As, In0.52Al0.48As, In0.53Ga0.47As, and In0.49Ga0.51P. Additionally, physically justifiable interpolation schemes are suggested to find the mobilities of various ternary and quaternary compounds (such as AlxGa1−xAs, In1−xGaxP, In1−xGaxAs, In1−xAlxAs, and In1−xGaxAsyP1−y) in the entire range of composition. The models are compared with numerous measured Hall data in the literature and very good agreement is observed. The limitations of the present model are also discussed. The results of this work should be extremely useful in device simulation packages, which are currently lacking a reliable mobility model for the above materials.

368 citations


Journal ArticleDOI
TL;DR: In this article, the authors measured U(VI) adsorption on hematite using EXAFS spectroscopy and electrophoresis under conditions relevant to surface waters and aquifers (0.01 to 10 μM dissolved uranium concentrations, in equilibrium with air, pH 4.5 to 8.5).

341 citations


Journal ArticleDOI
01 Oct 2000-Polymer
TL;DR: In this paper, the ternary mixture of benzoxazine, epoxy, and phenolic novolac resins is used for underfilling encapsulation and other highly filled systems.

321 citations


Journal ArticleDOI
TL;DR: In this article, a multicomponent extension to a multi-phase field model was proposed to simulate solidification and heat treatment of technical single crystal superalloys, which can be applied to any system if a thermodynamic database is available and is not restricted to a special formulation of the Gibbs energy.

139 citations


Journal ArticleDOI
26 Aug 2000-Langmuir
TL;DR: In this paper, the phase behavior and microstructure of two ternary systems consisting of Pluronic F127 (Poloxamer 407), water, and the pharmaceutically acceptable solvents propylene carbonate (4-methyl-1,3-dioxolan-2-one) or triacetin (glycerol triacetate) are presented.
Abstract: The evolution in the self-assembly of an amphiphilic poly(ethylene oxide)−poly(propylene oxide)−poly(ethylene oxide) (PEO-PPO-PEO) block copolymer in ternary systems with water and organic solvents of varying relative polarity is examined. The phase behavior and microstructure of two ternary systems consisting of Pluronic F127 (Poloxamer 407), water, and the pharmaceutically acceptable solvents propylene carbonate (4-methyl-1,3-dioxolan-2-one) or triacetin (glycerol triacetate) are presented. The microstructure of the lyotropic liquid crystalline phases formed and their characteristic length scales are determined from small-angle X-ray scattering (SAXS). The trends in the SAXS lattice spacing and the interfacial area per block copolymer molecule help establish the location of the solvents in the microstructure. The phase behavior of the two systems studied here is discussed in the context of ternary systems of Pluronic F127 with water and polar solvents (“glycols”, e.g., propylene glycol) or apolar organi...

125 citations


Journal ArticleDOI
TL;DR: In this paper, the evolution of ternary mixtures containing water, poly(ethylene oxide) (PEO) and dextran or electrolytes (NaCl, Na2SO4 or Li 2SO4), toward the formation of aqueous two-phase systems was investigated by calorimetry measuring enthalpies of solution for one of the components in water and in an aouous solution of the other component.
Abstract: The evolution of ternary mixtures containing water, poly(ethylene oxide) (PEO) and dextran or electrolytes (NaCl, Na2SO4 or Li2SO4), toward the formation of aqueous two-phase systems was investigated by calorimetry measuring enthalpies of solution for one of the components in water and in an aqueous solution of the other component. These values were then analyzed as enthalpies of transfer from water to aqueous solution of the second component, to probe the energy balance for the solvation of the transferred component between both states. The obtained results confirmed that enthalpic contributions are relevant to biphase formation in the presence of electrolytes, but much less important in mixtures of the two polymers. In all cases, phase separation was accompanied by an enthalpy increase, indicating that entropy increase is the driving force for aqueous two-phase systems formation. Moreover, based on enthalpy data, it was possible to assign different behavior to electrolytes capable of inducing aqueous tw...

123 citations


Journal ArticleDOI
TL;DR: Equilibrium metal uptake performance of a biosorbent prepared from Ascophyllum nodosum seaweed biomass was studied using aqueous solutions containing copper, cadmium, and zinc ions in binary and ternary mixtures.
Abstract: Equilibrium metal uptake performance of a biosorbent prepared from Ascophyllum nodosum seaweed biomass was studied using aqueous solutions containing copper, cadmium, and zinc ions in binary and ternary mixtures. Triangular equilibrium diagrams can graphically represent all the ternary equilibrium sorption data. Application of the multicomponent Langmuir model to describe the three-metal system revealed its nonideal characteristics, whereby the value of apparent dissociation constants for the respective metals differed for each system. This restricted the prediction of the ternary equilibria from the binary systems. However, some predictions of the ternary system behavior from the model were consistent with experimental data and with conclusions postulated from the three possible binary subsystems.

123 citations


Journal ArticleDOI
TL;DR: In this article, the authors examined the solidification behavior in the Mo-Si-B ternary system based on the microstructures of arc-cast alloys and identified several solidification characteristics using XRD, SEM and TEM.

119 citations


01 Jan 2000
TL;DR: In this article, the authors discuss certain ternary algebraic structures appearing more or less naturally in various domains of theoretical and mathematical physics, and draw attention to these algebras, which may find more interesting applications in the years to come.
Abstract: We discuss certain ternary algebraic structures appearing more or less naturally in various domains of theoretical and mathematical physics. Far from being exhaustive, this article is intended above all to draw attention to these algebras, which may find more interesting applications in the years to come.

Journal ArticleDOI
15 Dec 2000-EPL
TL;DR: In this paper, the nonreversing heat flow, ΔHnr(x) near Tg in ternary GexAsxSe1 − 2x glasses is examined by temperature-modulated differential scanning calorimetry.
Abstract: The non-reversing heat flow, ΔHnr(x) near Tg in ternary GexAsxSe1 − 2x glasses is examined by temperature-modulated differential scanning calorimetry. The ΔHnr(x) term shows a deep minimum (which is almost zero) in the 0.09 0.14) in the stressed rigid phase. Expressed in terms of mean coordination number, = 2 + 3x, the large width, Δ = rc(1) − rc(2) = 0.15, of the intermediate phase and its low onset value rc(1) = 2.27 are shown to be consistent with the presence of Se = As(Se1/2)3 units in addition to pyramidal As(Se1/2)3 and tetrahedral Ge(Se1/2)4 units in the stress-free backbone. The vanishing of ΔHnr(x) in the intermediate phase is in harmony with the notion that the number of Lagrangian constraints/atom exhausts the three available degrees of freedom, and leaves the backbone in a mechanically stress-free state.

Journal ArticleDOI
TL;DR: In this article, fully dense samples of Hf2PbC, Zr2SnC, Nb2Nc, Ti2SNC, HfNc and NbNc were fabricated by reactively HIPing the stoichiometric mixture of the corresponding elemental powders in the 1200-1325°C temperature range for 4-48 h.
Abstract: Predominantly single phase (92–94 vol.%), fully dense samples of Hf2SnC, Zr2SnC, Nb2SnC, Ti2SnC, Hf2PbC and Zr2PbC were fabricated by reactively HIPing the stoichiometric mixture of the corresponding elemental powders in the 1200–1325°C temperature range for 4–48 h. The latter two, fabricated here for the first time, required a further anneal of 48–96 h to increase the volume fraction of ternary phases. Hf2PbC and Zr2PbC are unstable in ambient atmospheres at room temperature. As a family these compounds are good electrical conductors; the lowest and highest values of the electrical conductivities were, respectively, 2.2×106 (Ω.m)−1 for Hf2SnC and 13.4×106 (Ω.m)−1 for Hf2PbC. The Vickers hardness values range from 3 to 4 GPa. All compounds are readily machinable. The Young's moduli of Zr2SnC, Nb2SnC and Hf2SnC are, respectively, 178, 216 and 237 GPa. The thermal coefficients of expansion, TCE's, of the ternaries scale with those of the corresponding binaries, and are relatively low for such readily machinable solids. The lowest TCE belonged to Nb2SnC [(7.8±0.2)×10−6 K−1], and the highest to Ti2SnC [(10±0.2)×10−6 K−1]. The TCE's of Hf and Zr containing ternaries cluster around (8.2±0.2)×10−6 K−1. All the synthesized ternary carbides were found to dissociate into the transition metal carbide and the A-group element in the 1250–1390 °C temperature range.

Journal ArticleDOI
TL;DR: In this article, a database of optical constants for sulfuric acid (c ≤ 80 wt %) and nitric acid, for temperatures 183 ≤ T ≤ 293 K were obtained.
Abstract: Fourier transform infrared transmission (FTIR) measurements of thin films of aqueous sulfuric and nitric acid and their ternary mixture were performed over a wide range of composition and temperature. On the basis of a systematic study of the spectra a database of optical constants for sulfuric acid (c ≤ 80 wt %) and nitric acid (c ≤ 50 wt %) for temperatures 183 ≤ T ≤ 293 K were obtained. A mixing rule is presented to calculate k(ν) and n(ν) spectra for H2SO4/HNO3/H2O solutions and validated against the new FTIR measurements of ternary solutions. This covers optical constants in the entire range of atmospheric relevance and is easily accessible for various applications, e.g., satellite aerosol observations.

Journal ArticleDOI
TL;DR: In this paper, the authors report on the crystal structure determination by Rietveld refinement on neutron and X-ray powder diffraction data, and show that the compound originally thought to be Ti3Al2N2 is Ti4AlN3.

Journal ArticleDOI
TL;DR: In this article, X-ray powder diffraction analysis of stoichiometric ternary compounds in the quasi-binary systems GeTe, Bi2Te3, SnTe, and PbBi2Te4 has been performed.

Journal ArticleDOI
TL;DR: In this article, the authors presented detailed information on the band structures of the III-nitride wurtzite ternary alloys, computed through the virtual crystal approximation approach.
Abstract: This work presents detailed information on the band structures of the III-nitride wurtzite ternary alloys, computed through the virtual crystal approximation approach. The key ingredient of this study is the set of realistic atomic effective potentials described in Part I of the present work, dedicated to the constituent binary compounds. The model relies on the linear interpolation of the structural parameters and of the local and nonlocal effective potentials: no further empirical corrections are included. The dependence on the mole fraction is computed for the energy gaps at all the high-symmetry points, the valence-band width, and the electron effective masses in the valleys relevant for carrier-transport simulation.

Journal ArticleDOI
TL;DR: In this paper, the ternary phase prism for low molecular weight poly(ethylene oxide), squalane, and poly(methylene oxide-b-ethylenepropylene) is presented.
Abstract: An investigation of the ternary phase prism for low molecular weight poly(ethylene oxide), squalane, and poly(ethylene oxide-b-ethylenepropylene) is presented. Comparisons are made between this ternary polymer system and classic water/oil/surfactant mixtures to establish further a universal phase diagram description for amphiphilic systems. A combination of visual isothermal measurements, small-angle X-ray scattering, small-angle neutron scattering, and dynamical mechanical spectrometry was used to characterize phases and determine phase boundaries. A rich phase diagram was revealed, including most of the equilibrium liquid crystalline phases associated with diblock copolymers, regions of two-phase and three-phase coexistence, and a bicontinuous microemulsion. Differences between this polymer phase diagram and those from water/oil/surfactant systems highlight the strong effect of water in the latter.

Journal ArticleDOI
TL;DR: In this article, the synergism in the glass transition temperature (Tg) of ternary systems based on benzoxazine (B), epoxy (E), and phenolic resins is reported.
Abstract: The synergism in the glass-transition temperature (Tg) of ternary systems based on benzoxazine (B), epoxy (E), and phenolic (P) resins is reported. The systems show the maximum Tg up to about 180 °C in BEP541 (B/E/P 5 5/4/1). Adding a small fraction of phenolic resin enhances the crosslink density and, therefore, the Tg in the copolymers of benzoxazine and epoxy resins. To obtain the ultimate Tg in the ternary systems, 6 -10 wt % phenolic resin is needed. The molecular rigidity from benzoxazine and the improved crosslink density from epoxy contribute to the synergistic behavior. The mechanical relaxation spectra of the fully cured ternary systems in a temperature range of 2140 to 350 °C show four types of relaxation transitions: g transition at 280 to 260 °C, b transition at 60 - 80 °C, a1 transition at 135-190 °C, and a2 transition at 290 -300 °C. The partially cured specimens show an additional loss peak that is frequency-independent as a result of the further curing process of the materials. The ternary systems have a potential use as electronic packaging molding compounds as well as other highly filled systems. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 1687-1698, 2000

Journal ArticleDOI
01 Sep 2000-Polymer
TL;DR: In this paper, phase morphology and mechanical properties of ternary blends consisting of polystyrene, SBR (styrene butadiene rubber) and different polyolefins (POs) have been studied.

Journal ArticleDOI
TL;DR: Most ternary mixtures were synergistic (significantly greater than the average of the three self-mixtures) to some degree, while more dyadic combinations of sweeteners tested previously exhibited synergism than ternARY combinations tested here.
Abstract: The purpose of the present study was to determine the degree of synergism of sweet taste among ternary mixtures of 14 sweeteners. A trained panel evaluated ternary mixtures of 14 sweeteners varying in chemical structure and type. The ternary mixtures that were tested were limited to those in which the compounds comprising the mixture were synergistic in binary combinations, according to an earlier study. All sweeteners in the ternary mixtures were isointense with 2% sucrose, according to a previously developed formulae. Each self-mixture was also tested (e.g. 2% sucrose + 2% sucrose + 2% sucrose). The triad with the highest mean sweetness intensity rating was alitame-neohesperidin dihydrochalcone-rebaudioside-A (10.8). This represents an increase of 99.4% when compared with the average of the self-mixtures. While this is greater than the maximum of 74% increase found for binary mixtures, more dyadic combinations of sweeteners tested previously exhibited synergism than ternary combinations tested here. However, most ternary mixtures were synergistic (significantly greater than the average of the three self-mixtures) to some degree.

Journal ArticleDOI
TL;DR: In this article, the Bozzolo-Ferrante-Smith (BFS) method was used to determine the site preference for ternary alloying additions over a range of compositions.

Journal ArticleDOI
TL;DR: In this paper, a modified UNIQUAC model is presented to accurately reproduce binary phase equilibria and ternary and quaternary liquid-liquid equilibrium ofaqueous and organic solutions.
Abstract: A modified form of the UNIQUAC model is presented to accurately reproducebinary phase equilibria and ternary and quaternary liquid-liquid equilibria ofaqueous and organic solutions. The model gives a good representation in thereproduction of binary coexistence curves over a wide temperature range usingtemperature-dependent parameters and of binary vapor-liquid equilibria usingtwo binary energy parameters, and in the correlation of ternary and quaternaryliquid-liquid equilibria using ternary and quaternary parameters, in addition tobinary parameters. The quaternary calculated results are compared with thoseobtained from the modified Wilson and extended UNIQUAC models.

Journal ArticleDOI
TL;DR: An icosahedral quasicrystalline phase was confirmed as a primary precipitation phase in melt-spun Zr70Ni10M20 (M=Pd, Au and Pt) ternary metallic glasses with two-stage crystallization process.
Abstract: An icosahedral quasicrystalline phase was confirmed as a primary precipitation phase in melt-spun Zr70Ni10M20 (M=Pd, Au and Pt) ternary metallic glasses with two-stage crystallization process. The onset temperature of the transformation from amorphous to icosahedral phase are 687 K for Pd, 754 K for Au and 783 K for Pt at a heating rate of 0.67 K s−1. The size of the icosahedral particles is in the range of 5–20 nm. The second crystallization reaction results in the formation of Zr2Ni+Zr2Pd and Zr2Ni+ZrPt phases in the Zr–Ni–Pd and Zr–Ni–Pt alloys, respectively, and Zr3Au phase in the Zr–Ni–Au alloy through a single exothermic reaction. The formation of nanoscale icosahedral phase indicates the possibility that icosahedral short-range order exists in the glassy state.

Journal ArticleDOI
TL;DR: In this article, ternary transition-metal nitride coatings of (Ti,Zr)N,(Ti,Nb)N and (Zr, Nb) N were deposited using a triple cathode vacuum arc deposition system by simultaneously operating two cathodes of the appropriate metals in a low-pressure nitrogen background.
Abstract: Ternary transition-metal nitride coatings of (Ti,Zr)N, (Ti,Nb)N and (Zr,Nb)N were deposited using a triple cathode vacuum arc deposition system by simultaneously operating two cathodes of the appropriate metals in a low-pressure nitrogen background. The magnetically collimated plasma flux distribution was measured using a 13-element ion saturation current probe. The microstructure, composition, and hardness of the coatings were determined using X-ray diffraction, Auger electron spectroscopy, and Vickers indentation, respectively. The plasma flux distribution had two peaks whose relative positions were related to the two cathodes. Coatings applied to extended substrates had a compositional gradient. In almost all cases, the ternary nitrides had a single-phase solid-solution microstructure, whose lattice constants had values intermediate between those of the parent binary nitrides. The ternary coatings were considerably harder than either of the parent binary nitrides. (Ti,Nb)N had the highest microhardness: ∼50 GPa.

Journal ArticleDOI
TL;DR: In this paper, the preferential solvation of the N-methylacetamide molecule has been investigated in the binary and ternary mixtures containing N- methylacetamide (NMA), aliphatic alcohol and water.
Abstract: Using the Kirkwood–Buff theory of solutions, the preferential solvation of the N-methylacetamide molecule has been investigated in the binary and ternary mixtures containing N-methylacetamide (NMA), aliphatic alcohol and water. The results are compared with those obtained previously for N-methylformamide (NMF) and N,N-dimethylformamide (DMF). The thermodynamic investigations, based on the Kirkwood–Buff theory of solutions, lead to the unexpected conclusion that both NMA and DMF are solvated in the investigated binary and ternary mixtures in a very similar manner, but solvation of NMF differs from other amides. For all the investigated amides, the local mole fractions differ only slightly from the bulk ones—the deviations are only a few per cent or less. Moreover, for the {amide+methanol} binary mixtures, where amide=NMF, DMF and NMA, molecular dynamics calculations at xamide=0.518 were performed. From the obtained molecule–molecule radial distribution functions (rdf) and atom–atom rdf, it was possible to estimate the local mole fractions around the amide molecule, the orientation effects of molecules within the solvation shell, and a possibility of the formation of complexes. The general picture obtained from analysis of the molecular dynamics results is consistent with the deductions derived from thermodynamic data.

Journal ArticleDOI
TL;DR: In this paper, the ternary originally thought to be Ti3Al2N2 was Ti4AlN3−x and was further annealed under Ar for 168 hours at 1598 K.
Abstract: Recently, we have shown that the ternary originally thought to be Ti3Al2N2 was Ti4AlN3.[1] In this work, polycrystalline, fully dense, predominantly single-phase bulk samples of Ti4AlN3−x were fabricated by reactive hot isostatic pressing (“hipping”) of AlN, TiN, and Ti or TiH2 powders at 1275 °C for 24 hours at 70 MPa. The pressed samples were further annealed under Ar for 168 hours at 1598 K, to obtain predominantly single-phase samples. The current Ti-Al-N isothermal (1598 K) phase diagram, based on Ti3Al2N2, has been revised to take into account the presence of Ti4AlN3−x instead and to reflect the fact that Ti2AlN is in equilibrium with all the binary and ternary phases in the Ti-Al-N system except AlN.

Journal ArticleDOI
TL;DR: In this article, microstructural results in as-cast and annealed samples are discussed, and the dominant equilibrium phases identified are the C 14 -like Laves phase, a Ti 2 Ni-like phase, α(Ti/Zr), the b.c. 1/1 W-phase and the i-phase.
Abstract: Equilibrium phase formation is reported for ternary Ti–Zr–Ni alloys near the i-phase-forming composition, for temperature slices between 500 and 700°C. Selected microstructural results in as-cast and annealed samples are discussed. Dominant equilibrium phases identified are the C 14 -like Laves phase, a Ti 2 Ni-like phase, α(Ti/Zr), the b.c.c. 1/1 W-phase and the i-phase. The i-phase forms over a small compositional range from a high-temperature equilibrium phase mixture of the Laves and α(Ti/Zr) solid solution phases. Lower annealing treatments have not been found to transform the i-phase, suggesting that in this alloy, the quasicrystal phase might be the ground state phase. Additions of small amounts of Pb and Pd, 1–2 at.%, are demonstrated to substantially effect the equilibrium phase formation for the i-phase and the W-phase. The addition of 1 at.% of Pb significantly orders the i-phase structure.

Journal ArticleDOI
TL;DR: In this paper, a procedure for the simultaneous prediction of fluid and solid-fluid equilibria of light gases-heavy hydrocarbons systems under pressure is presented. But this procedure was tested for several binary and ternary systems as well as multi-component systems.

Journal ArticleDOI
TL;DR: In this article, a series of compounds YbxM4Sb12, were synthesised by reaction sintering, revealing a gradual decrease of the Yb-content from x ≥ 0.1 (Rh) to approximately 0.02 (Ir).
Abstract: A series of compounds YbxM4Sb12, were synthesised by reaction sintering. From Rietveld refinements isotypism was determined in all cases with the LaFe4P12-(skutterudite)-type, space group $${\mathop{\rm Im} olimits} \overline 3 $$ - No. 204. These refinements also served to derive the Yb-content in the samples. There is a systematic trend for the Yb-occupancy in the parent lattice M4Sb12, revealing a gradual decrease of the Yb-content from x =0.8 (M=Fe), x =0.5 (FeCo), x =0.2 (Co), x =0.1 (Rh) to $$x \approx 0.02$$ (Ir). This dependency seems to correlate with the thermal stability of the ternary compounds: a true ternary compound forms for M =Fe, whilst for M = Co stable binary skutterudite compounds MSb3 already exist. Measurements of various bulk properties revealed the absence of any long range magnetic order in this series of compounds. While the samples rich in Yb behave metallic like, the Rh and Ir based skutterudites show a semiconducting-like resistivity which at lower temperatures is characterised by variable range hopping in the presence of strong Coulomb interaction. Although Yb0.1Rh4Sb12 exhibits a Seebeck coefficient up to about 150 μV/K, figures of merit ZT generally are below 0.1 near room temperature, primarily due to the large resistivities of the sintered material.