Pressure-dependent melting and crystallization of B2-NiAl from neural-network molecular dynamics
Abstract
We investigate pressure-dependent melting of ordered B2-NiAl using neural-network molecular dynamics with a Deep Potential interatomic model. Melting temperatures are determined from two-phase solid-liquid coexistence simulations over a broad pressure range, yielding the melting curve Tm(P). Relative to available experimental and previous molecular-dynamics results, the present calculations predict a stronger increase of the melting temperature with pressure at elevated compression. To assess the thermodynamic consistency of the calculated melting line, we evaluate the enthalpy and volume changes upon melting and compare the Clapeyron slope with the derivative of the fitted Tm(P) curve. The two estimates are in good agreement over most of the investigated pressure range, supporting the internal consistency of the coexistence results. To probe the character of melting, we perform a layer-resolved composition analysis of the coexistence configurations and find that the coexisting liquid remains essentially equiatomic at all studied pressures, with deviations of the aluminum fraction from the stoichiometric value not exceeding 5×10−3. This provides direct atomistic evidence that melting of B2-NiAl remains congruent within the present model. Together, these results establish a thermodynamically consistent pressure-dependent melting description of B2-NiAl and clarify the character of its melting under compression.
Related
- Melting Behavior and Phase Stability of CaO from Neural Network Potentials: a Molecular Dynamics Study
- Helium Compression Chamber: an ab initio molecular dynamics approach to chemical reactions under pressure
- Libron-phonon coupling and hydrogen-bond dynamics in the vacancy-ordered perovskite (NH4)2SnCl6: a temperature- and pressure-dependent Raman study
- Interaction-Dependent Molecular Probing of Heterogeneous Glassy Dynamics in Polymer Melts
- A wide-range temperature-dependent deep potential for sodium with near-experimental accuracy from melting to the critical point
BibTeX
@misc{onegin2026pressuredependent,
title = {{Pressure-dependent melting and crystallization of B2-NiAl from neural-network molecular dynamics}},
author = {A. S. Onegin and P. R. Levashov and N. M. Chtchelkatchev},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.19355},
eprint = {2609.19355},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.19355},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Pressure-dependent melting and crystallization of B2-NiAl from neural-network molecular dynamics
AU - A. S. Onegin
AU - P. R. Levashov
AU - N. M. Chtchelkatchev
PY - 2026
DA - 2026/09/16
PB - arXiv
DO - 10.48550/arxiv.2609.19355
UR - https://arxiv.org/abs/2609.19355
AB - We investigate pressure-dependent melting of ordered B2-NiAl using neural-network molecular dynamics with a Deep Potential interatomic model. Melting temperatures are determined from two-phase solid-liquid coexistence simulations over a broad pressure range, yielding the melting curve T_m(P). Relative to available experimental and previous molecular-dynamics results, the present calculations predict a stronger increase of the melting temperature with pressure at elevated compression. To assess the thermodynamic consistency of the calculated melting line, we evaluate the enthalpy and volume changes upon melting and compare the Clapeyron slope with the derivative of the fitted T_m(P) curve. The two estimates are in good agreement over most of the investigated pressure range, supporting the internal consistency of the coexistence results. To probe the character of melting, we perform a layer-resolved composition analysis of the coexistence configurations and find that the coexisting liquid remains essentially equiatomic at all studied pressures, with deviations of the aluminum fraction from the stoichiometric value not exceeding 5×10^−3. This provides direct atomistic evidence that melting of B2-NiAl remains congruent within the present model. Together, these results establish a thermodynamically consistent pressure-dependent melting description of B2-NiAl and clarify the character of its melting under compression.
ER -