A general approach for calculating melt–solid impurity segregation coefficients based on thermodynamic integration

ABSTRACTLanthanum chloride was synthesized by reacting La2O3 with CCl4. Purification carried out by zone refining resulted in reduction of Nd and Eu concentrations by at least a factor of 103. Impurity segregation coefficients were calculated from the concentration profiles in the charge measured by neutron activation analysis. Values of 0.85, 0.5, and 0.15 were found for Ce, Nd and Eu while a value of 0.65 was obtained for Pr from a plot of measured distribution coefficient versus ionic radius. These results show the feasibility of removing rare earth impurities to the ppb level from LaCl3. After purification, LaC13 is converted to LaF3

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TI/PIMC METHOD WITH THE TAKAHASHI–IMADA APPROXIMATION FOR THE EQUILIBRIUM CONSTANT OF THE O + HCl ⇌ OH + Cl REACTION

Journal of Theoretical and Computational Chemistry ◽

10.1142/s0219633613500260 ◽

2013 ◽

Vol 12 (04) ◽

pp. 1350026 ◽

Cited By ~ 1

Author(s):

MARCIN BUCHOWIECKI

Keyword(s):

Monte Carlo ◽

Temperature Dependence ◽

Equilibrium Constant ◽

Path Integral ◽

Thermodynamic Integration ◽

Partition Functions ◽

Integration Path ◽

Path Integral Monte Carlo

The thermodynamic integration/path integral Monte Carlo (TI/PIMC) method of calculating the temperature dependence of the equilibrium constant quantum mechanically is applied to O + HCl ⇌ OH + Cl reaction. The method is based upon PIMC simulations for energies of the reactants and the products and subsequently on thermodynamic integration for the ratios of partition functions. PIMC calculations are performed with the primitive approximation (PA) and the Takahashi–Imada approximation (TIA).

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Free Energy Simulations of Methane Solvation: A Study of Integrand Convergence Properties Using Thermodynamic Integration

10.1063/1.41308 ◽

1991 ◽

Author(s):

S. Fleischman

Keyword(s):

Free Energy ◽

Thermodynamic Integration ◽

Convergence Properties ◽

Energy Simulations

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Structure, Dynamics, and Hydration Free Energy of Carbon Dioxide in Aqueous Solution: A Quantum Mechanical/Molecular Mechanics Molecular Dynamics Thermodynamic Integration (QM/MM MD TI) Simulation Study

Journal of Chemical Theory and Computation ◽

10.1021/acs.jctc.8b00557 ◽

2018 ◽

Vol 14 (12) ◽

pp. 6472-6483 ◽

Cited By ~ 4

Author(s):

Niko Prasetyo ◽

Thomas S. Hofer

Keyword(s):

Carbon Dioxide ◽

Molecular Dynamics ◽

Aqueous Solution ◽

Free Energy ◽

Molecular Mechanics ◽

Simulation Study ◽

Thermodynamic Integration ◽

Quantum Mechanical ◽

Hydration Free Energy ◽

Structure Dynamics

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Concentration-Independent Solute Segregation in Laser Annealing of Semiconductor Crystals

MRS Proceedings ◽

10.1557/proc-23-193 ◽

1983 ◽

Vol 23 ◽

Author(s):

Jun-ichi Chikawa ◽

Fumio Sato ◽

Tadasu Sunada

Keyword(s):

Mixed Crystal ◽

Laser Annealing ◽

Solute Segregation ◽

Atomic Processes ◽

Segregation Coefficient ◽

Depth Profiles ◽

Semiconductor Crystals ◽

Impurity Segregation ◽

Solute Atoms ◽

Interfacial Segregation

ABSTRACTAtomic processes at the interface in regrowth following laser induced melting were investigated by observing behavior of impurity segregation. The interfacial segregation coefficient k* was obtained from depth profiles of solute atoms redistributed by laser irradiation of uniformly doped Si, Ge, and GayAl1−yAs crystals. It was found that k*=k0 for B in Si, Ga in Ge ih the growth rate range of 1 m/s. It is concluded that rapid growth freezes a state of liquid monolayer adjacent to the interface which has the character of ideal solution from dilute to eutectic composition for dopant-silicon systems and in the entire range of composition for the mixed crystal.

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