Thermodynamic description of Ge-Mn-Si

ABSTRACTLiterature data of the Mn-Si system is analyzed and discordances are pointed out. First principles calculations are performed to clarify the enthalpies of formation of the intermetallic phases. Especially the enthalpies of formation of the various possible structures of the MnSix are discussed. On the basis of these new data, a thermodynamic description of the Gibbs energy of the phases is performed using the Calphad method. The system Ge-Mn is also assessed using the Calphad method for the first time.The mixing enthalpy in the D88 solid solution is calculated between Mn5Ge3 and Mn5Si3 by DFT calculations.Finally a thermodynamic description of the ternary system is suggested. Especially the solubility of germanium in MnSix is modeled.

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Thermodynamic description of the Al-Cu-Yb ternary system supported by first-principles calculations

Journal of Mining and Metallurgy Section B Metallurgy ◽

10.2298/jmmb150709013h ◽

2016 ◽

Vol 52 (2) ◽

pp. 177-183 ◽

Cited By ~ 2

Author(s):

G. Huang ◽

L. Liu ◽

L. Zhang ◽

Z. Jin

Keyword(s):

Ternary System ◽

First Principles ◽

Thermodynamic Description ◽

Theoretical Data ◽

Intermetallic Phases ◽

Calphad Method ◽

First Principles Calculations ◽

Self Consistent ◽

Ternary Intermetallic Compounds ◽

Phase Relationships

Phase relationships of the ternary Al-Cu-Yb system have been assessed using a combination of CALPHAD method and first principles calculations. A self-consistent thermodynamic parameter was established based on the experimental and theoretical information. Most of the binary intermetallic phases, except Al3Yb, Al2Yb, Cu2Yb and Cu5Yb, were assumed to be zero solubility in the ternary system. Based on the experimental data, eight ternary intermetallic compounds were taken into consideration in this system. Among them, three were treated as line compounds with large homogeneity ranges for Al and Cu. The others were treated as stoichiometric compounds. The calculated phase diagrams were in agreement with available experimental and theoretical data.

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Thermodynamic modeling of the In-Sc and In-Y systems supported by first-principles calculations

Journal of Mining and Metallurgy Section B Metallurgy ◽

10.2298/jmmb171121004h ◽

2018 ◽

Vol 54 (2) ◽

pp. 161-167 ◽

Cited By ~ 1

Author(s):

Z. Hu ◽

C. Huang ◽

J. Tu ◽

Y. Huang ◽

A. Dong

Keyword(s):

Intermetallic Compounds ◽

Thermodynamic Modeling ◽

First Principles ◽

Regular Solution Model ◽

Calphad Method ◽

Enthalpies Of Formation ◽

Thermodynamic Optimization ◽

First Principles Calculations ◽

Self Consistent ◽

Good Agreement

Based on an assessment of the phase equilibria and thermodynamic data in the literature, the thermodynamic modeling of the In?Sc and In?Y systems was carried out by means of the calculation of phase diagram (CALPHAD) method supported by first-principles calculations. The solution phases, i.e., liquid, (In), (?Sc), (?Sc), (?Y) and (?Y), were modeled with the substitutional regular solution model. Ten intermetallic compounds, including InSc3, InSc2, In4Sc5, InSc, In2Sc, In3Sc, InY2, InY, In5Y3, and In3Y were described as stoichiometric phases, while In3Y5 was modeled with a sublattice model with respect to its homogeneity range. The enthalpies of formation of the intermetallic compounds at 0 K were computed using firstprinciple calculations and were used as input for the thermodynamic optimization. A set of self-consistent thermodynamic parameters for both the In?Sc and In?Y systems were obtained and the calculated phase diagrams are in good agreement with the experimental data.

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Thermodynamic assessment of the Pb-Sr system

Journal of Mining and Metallurgy Section B Metallurgy ◽

10.2298/jmmb170302013z ◽

2017 ◽

Vol 53 (3) ◽

pp. 179-187 ◽

Cited By ~ 1

Author(s):

H. Zhang ◽

C. Zhang ◽

W.W. Wang ◽

Y. Du ◽

P. Zhou ◽

...

Keyword(s):

First Principles ◽

Thermodynamic Assessment ◽

Thermodynamic Description ◽

Experimental Information ◽

Enthalpies Of Formation ◽

First Principles Calculations ◽

Exponential Polynomials ◽

Self Consistent ◽

Five Phases ◽

Measured Phase Diagram

The Pb-Sr system has been critically reviewed and modeled by means of the CALPHAD (CALculation of PHAse Diagrams) approach. It contains seven stoichiometric compounds, i.e. SrPb3, Sr3Pb5, Sr2Pb3, SrPb, Sr5Pb4, Sr5Pb3 and Sr2Pb, in which the SrPb3 and Sr2Pb phases melt congruently, and the other five phases form via peritectic reactions. The enthalpies of formation for the intermetallic compounds at 0 K are provided by first-principles calculations. The liquid, fcc and bcc phases are modeled as substitutional solution phases. Both Redlich-Kister and exponential polynomials are used to describe the excess Gibbs energy of the liquid. Two sets of self-consistent thermodynamic parameters are obtained by considering reliable experimental data and the computed enthalpies of formation. Comprehensive comparisons between the calculated and measured phase diagram and thermodynamic data show that the experimental information is satisfactorily accounted for by the present thermodynamic description.

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The origins of charge separation in anisotropic facet photocatalysts investigated through first-principles calculations

RSC Advances ◽

10.1039/d1ra01711j ◽

2021 ◽

Vol 11 (30) ◽

pp. 18500-18508

Author(s):

Shun-Chiao Chan ◽

Yu-Lin Cheng ◽

Bor Kae Chang ◽

Che-Wun Hong

Keyword(s):

First Principles ◽

Charge Separation ◽

First Principles Calculations ◽

Design And Development ◽

First Time

The anisotropic (110)/(100) facet junction built-in potential in SrTiO3 is estimated at 2.9 V using DFT for the first time, which can help in further design and development of efficient photocatalysts using such anisotropic-facet engineering.

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First-principles calculations of LaNi4Al–H solid solution and hydrides

Acta Materialia ◽

10.1016/j.actamat.2005.09.027 ◽

2006 ◽

Vol 54 (2) ◽

pp. 465-472 ◽

Cited By ~ 21

Author(s):

R.J. Zhang ◽

Y.M. Wang ◽

D.M. Chen ◽

R. Yang ◽

K. Yang

Keyword(s):

Solid Solution ◽

First Principles ◽

First Principles Calculations

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Remarkable improvement in phosgene detection with a defect-engineered phosphorene sensor: first-principles calculations

Physical Chemistry Chemical Physics ◽

10.1039/d0cp00427h ◽

2020 ◽

Vol 22 (17) ◽

pp. 9677-9684 ◽

Cited By ~ 6

Author(s):

Mehdi Ghambarian ◽

Zahra Azizi ◽

Mohammad Ghashghaee

Keyword(s):

Density Functional Theory ◽

First Principles ◽

Density Functional ◽

First Principles Calculations ◽

Defect Engineering ◽

Functional Theory ◽

Remarkable Improvement ◽

Black Phosphorene ◽

First Time ◽

Theory Framework

A drastic improvement in the phosgene sensitivity of black phosphorene with defect engineering is reported for the first time within a periodic density functional theory framework.

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Calphad description of the Ge-Mn system

MRS Proceedings ◽

10.1557/opl.2014.444 ◽

2014 ◽

Vol 1642 ◽

Author(s):

Alexandre Berche ◽

Jean-Claude Tédenac ◽

Philippe Jund ◽

Stéphane Gorsse

Keyword(s):

Phase Diagram ◽

Liquid Phase ◽

Thermodynamic Properties ◽

Gibbs Energy ◽

Critical Review ◽

Thermodynamic Description ◽

Calphad Method ◽

Review Of The Literature ◽

Solid Phases

ABSTRACTThe germanium-manganese system has been experimentally studied but no Calphad description is available yet. After a critical review of the literature concerning the phase diagram and the thermodynamic properties, a thermodynamic description of the Gibbs energy of the phases is performed using the Calphad method. The liquid phase is described with an associated model and the variation to the stoichiometry of the solid phases is taken into account.

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