Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: First Principles Study of the Structural, Mechanical, Electronic, and
  Lattice Dynamical Properties of the Half-Heusler Alloys ZrCoY (Y=Sb, Bi )   First-principles calculation has led to significant discoveries in materials
science. Half heusler (HH) alloys, which are potential thermoelectric materials
have demonstrated significant improvements in thermoelectric performance owing
to their thermal stability, mechanical strength, and moderate ZT. Using Density
Functional Theory (DFT), the structural, mechanical, electronic, and lattice
dynamical properties of cubic Half Heusler alloys ZrCoY (Y=Sb, Bi) have been
investigated. The unknown exchange-correlation functional is approximated using
the generalized gradient approximation (GGA) pseudopotential plane-wave
approach. The structural parameters, that is, equilibrium lattice constant,
elastic constants, and their derivatives are consistent with reported
experimental and theoretical studies where available. Mechanical properties
such as anisotropy factor A, shear modulus G, bulk modulus B, Youngs modulus E,
and Poisons ratio n, are calculated using the Voigt-Reuss-Hill average approach
based on elastic constants. The Debyes temperature, as well as longitudinal and
transverse sound velocities, are predicted from elastic constants at GGA-PBE
and GW approximations. The study of elastic constants showed that the compounds
are mechanically stable, and the phonon dispersion study showed that they are
dynamically stable as well. The ductility and anisotropic nature of the
compounds are confirmed by the elastic constants and mechanical properties.

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The categories of this paper are: astro-ph
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The categories of this paper are: hep-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: dg-ga
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The categories of this paper are: hep-ex
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The categories of this paper are: hep-lat
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The categories of this paper are: eess
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The categories of this paper are: math
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The categories of this paper are: econ
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The categories of this paper are: chem-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: quant-ph
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The categories of this paper are: adap-org
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The categories of this paper are: atom-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: q-bio