TY - JOUR
T1 - Structural and thermodynamic properties of compounds in the Mg-B-C system from first-principles calculations
AU - Saengdeejing, Arkapol
AU - Wang, Yi
AU - Liu, Zi Kui
N1 - Funding Information:
This work is funded by the National Science Foundation (NSF) through Focused Research Group (FRG) grant DMR-0514592 led by Prof. David Larbalestier. First-principles calculations were carried out on the LION clusters at the Pennsylvania State University supported in part by the NSF grants ( DMR-9983532, DMR-0122638 , and DMR-0205232 ) and in part by the Materials Simulation Center and the Graduate Education and Research Services at the Pennsylvania State University. We would also like to thank Dr. Raymundo Arroyave from Texas A&M University, Dr. Shunli Shang and James Saal from our group for stimulating discussions.
PY - 2010/5
Y1 - 2010/5
N2 - To understand the effects of carbon doping on the performance of MgB2 superconductors, the structure and thermodynamic properties of the key compounds in the Mg-B-C system need to be investigated. MgB2C2 is the only known ternary compound in this system, but no experimental data can be found in the literature. Using the first-principles phonon, we have calculated the elastic constant, enthalpy, entropy, heat capacity of the MgB2C2 compound along with pure Mg and the MgB2, MgC2, and Mg2C3 compounds that also appear in the Mg-B-C ternary system. The calculated lattice parameters and enthalpies of formation at 298 K show good agreement with available experimental data. For Mg and MgB2, the calculated thermodynamic properties agree with the experiment very well. For MgC2 and Mg2C3, the calculated enthalpies of formation are positive, indicating they are unlikely to form in equilibrium with respect to the pure elements.
AB - To understand the effects of carbon doping on the performance of MgB2 superconductors, the structure and thermodynamic properties of the key compounds in the Mg-B-C system need to be investigated. MgB2C2 is the only known ternary compound in this system, but no experimental data can be found in the literature. Using the first-principles phonon, we have calculated the elastic constant, enthalpy, entropy, heat capacity of the MgB2C2 compound along with pure Mg and the MgB2, MgC2, and Mg2C3 compounds that also appear in the Mg-B-C ternary system. The calculated lattice parameters and enthalpies of formation at 298 K show good agreement with available experimental data. For Mg and MgB2, the calculated thermodynamic properties agree with the experiment very well. For MgC2 and Mg2C3, the calculated enthalpies of formation are positive, indicating they are unlikely to form in equilibrium with respect to the pure elements.
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U2 - 10.1016/j.intermet.2009.12.015
DO - 10.1016/j.intermet.2009.12.015
M3 - Article
AN - SCOPUS:77950023070
SN - 0966-9795
VL - 18
SP - 803
EP - 808
JO - Intermetallics
JF - Intermetallics
IS - 5
ER -