pith. sign in

arxiv: 2606.19582 · v1 · pith:G54LLX44new · submitted 2026-06-17 · ❄️ cond-mat.mtrl-sci

Deposition and Growth of the AlCoCuFeNi High-Entropy Alloy Thin Film: Molecular Dynamics Simulation

Oleksandr I. Kushnerov , Valerij F. Bashev , Sergey I. Ryabtsev This is my paper

Pith reviewed 2026-06-26 19:49 UTC · model grok-4.3

classification ❄️ cond-mat.mtrl-sci
keywords high-entropy alloythin filmmolecular dynamicsAlCoCuFeNisilicon substratephase formationradial distribution functioncrystallization
0
0 comments X

The pith

Molecular dynamics simulation shows the AlCoCuFeNi high-entropy alloy film on silicon develops face-centered cubic, body-centered cubic, hexagonal close-packed, and amorphous phases after 50 nanoseconds.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper models the deposition and growth of an AlCoCuFeNi thin film on a silicon (100) substrate using molecular dynamics. Small clusters form early in the process, and crystallization begins after roughly 5 nanoseconds once clusters reach about 2 nanometers across. By the end of the 50-nanosecond run the film contains four phases whose nearest-neighbor distances and lattice parameters are extracted from the radial distribution function. A reader would care because the work supplies a concrete computational picture of how a multi-principal-element alloy organizes itself during thin-film growth on silicon.

Core claim

The simulation demonstrates that during deposition small clusters form at the first stage, crystallization starts after approximately 5 ns when the characteristic cluster size is about 2 nm, and at the end of 50 ns the film contains face-centered cubic, body-centered cubic, hexagonal close-packed, and amorphous phases whose lattice parameters are estimated from the radial distribution function.

What carries the argument

Molecular dynamics simulation that employs the embedded atom model for interactions among Al, Co, Cu, Fe, and Ni atoms, the Lennard-Jones potential for metal-silicon interactions, and the Stillinger-Weber potential for silicon-silicon interactions, run for a total of 50 ns.

If this is right

  • The final film contains a mixture of face-centered cubic, body-centered cubic, hexagonal close-packed, and amorphous phases.
  • Crystallization begins after about 5 ns once clusters reach roughly 2 nm in size.
  • Radial distribution function analysis yields nearest-neighbor distances and lattice parameters for the observed phases.
  • Cluster formation occurs in the initial stage of deposition on the silicon (100) substrate.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • The same simulation protocol could be rerun at different substrate temperatures or deposition rates to map how the phase mixture changes.
  • The coexistence of multiple phases suggests that high-entropy alloy films on silicon may routinely contain grain boundaries and amorphous regions that affect mechanical or electronic properties.
  • Direct comparison of the simulated lattice parameters with measured values from a real film would test whether the chosen potentials remain reliable for other high-entropy compositions.

Load-bearing premise

The embedded atom, Lennard-Jones, and Stillinger-Weber potentials accurately represent the atomic forces and energies that govern the real deposition process.

What would settle it

An experimental deposition of AlCoCuFeNi on Si(100) followed by X-ray diffraction or electron microscopy that either confirms or fails to detect the simultaneous presence of face-centered cubic, body-centered cubic, hexagonal close-packed, and amorphous phases in the film.

read the original abstract

The growth of a thin film of a high-entropy AlCoCuFeNi alloy on a silicon (100) substrate was studied using molecular dynamics modeling. The simulation was carried out using the embedded atom model to describe the interactions among Al, Co, Cu, Ni, and Fe atoms. The interaction between Al, Co, Cu, Fe, Ni atoms and the Si substrate was modeled using the Lennard-Jones potential, while the interaction between silicon atoms was described using the Stillinger-Weber potential. The total simulation time was 50 ns. It was found that small clusters were formed at the first stage of deposition and that crystallization started after approximately 5 ns of simulation, when the characteristic cluster size was about 2 nm. At the end of the simulation, after 50 ns of modeling, the simulated film contained face-centered cubic, body-centered cubic, hexagonal close-packed, and amorphous phases. Analysis of the radial distribution function made it possible to determine nearest-neighbor distances and estimate the lattice parameters of these phases.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

3 major / 1 minor

Summary. The manuscript reports a 50 ns molecular dynamics simulation of AlCoCuFeNi high-entropy alloy thin-film deposition on Si(100) using the embedded-atom method for metal-metal interactions, Lennard-Jones for metal-Si, and Stillinger-Weber for Si-Si. It describes initial cluster formation followed by crystallization after ~5 ns (cluster size ~2 nm) and concludes that the final film contains coexisting FCC, BCC, HCP, and amorphous phases whose lattice parameters are estimated from radial distribution function peaks.

Significance. If the mixed potentials are shown to be reliable, the work would supply atomistic detail on the sequence of cluster nucleation, crystallization onset, and multi-phase coexistence during HEA film growth on silicon, a topic of practical interest for thin-film materials. The simulation is strictly forward (no parameters fitted to the observed phases), which is a methodological strength.

major comments (3)
  1. [Abstract] Abstract: The central claim that the 50 ns film contains FCC, BCC, HCP, and amorphous phases rests on the assumption that the EAM + LJ + SW combination correctly reproduces metal-metal, metal-Si, and Si-Si energetics and barriers; no validation of the cross terms or of the quinary HEA on Si(100) against DFT or experiment is provided.
  2. [Abstract] Abstract: Phase identification and lattice-parameter extraction are performed exclusively via RDF peak positions; without supplementary metrics (e.g., common-neighbor analysis, bond-angle distributions, or direct visualization of atomic environments) the assignment of distinct crystalline phases versus amorphous regions cannot be independently verified.
  3. [Abstract] Abstract: No error bars, convergence tests with respect to system size, deposition rate, or multiple independent runs are reported, leaving the robustness of the reported phase mixture and the 5 ns crystallization onset unquantified.
minor comments (1)
  1. [Abstract] The abstract would be clearer if it stated the substrate temperature, deposition flux, and total number of deposited atoms.

Simulated Author's Rebuttal

3 responses · 0 unresolved

We thank the referee for the constructive comments on our manuscript. We address each major comment point by point below, indicating planned revisions where appropriate.

read point-by-point responses

  1. Referee: The central claim that the 50 ns film contains FCC, BCC, HCP, and amorphous phases rests on the assumption that the EAM + LJ + SW combination correctly reproduces metal-metal, metal-Si, and Si-Si energetics and barriers; no validation of the cross terms or of the quinary HEA on Si(100) against DFT or experiment is provided.

    Authors: We agree that direct validation of the mixed potentials against DFT or experiment for this specific system is absent from the manuscript. The potentials were selected from established parameterizations in the literature for related metallic and metal-semiconductor systems. In the revised manuscript we will expand the Methods section with an explicit discussion of this choice, cite supporting references, and add a clear statement of the limitation. We will also revise the abstract to qualify the phase claims accordingly. revision: yes

  2. Referee: Phase identification and lattice-parameter extraction are performed exclusively via RDF peak positions; without supplementary metrics (e.g., common-neighbor analysis, bond-angle distributions, or direct visualization of atomic environments) the assignment of distinct crystalline phases versus amorphous regions cannot be independently verified.

    Authors: The referee is correct that RDF provides only indirect support for phase assignment. In the revised manuscript we will add common-neighbor analysis and selected atomic-environment visualizations to the Results section to supply independent verification of the FCC, BCC, HCP, and amorphous regions. revision: yes

  3. Referee: No error bars, convergence tests with respect to system size, deposition rate, or multiple independent runs are reported, leaving the robustness of the reported phase mixture and the 5 ns crystallization onset unquantified.

    Authors: We acknowledge that the absence of ensemble statistics and convergence tests limits the ability to quantify robustness. The reported results derive from a single 50 ns trajectory. In the revision we will insert a dedicated paragraph in the Discussion section that addresses this limitation, notes the computational cost that precluded additional runs, and qualifies the reported onset time and phase fractions as qualitative observations from the available data. revision: partial

Circularity Check

0 steps flagged

No circularity: forward MD simulation with external potentials

full rationale

The paper reports results from a standard forward molecular dynamics run using externally specified potentials (EAM for metal-metal, LJ for metal-Si, SW for Si-Si) over 50 ns. The phases (FCC, BCC, HCP, amorphous) and RDF-derived lattice parameters are direct simulation outputs, not fitted to the target film structure, not defined in terms of themselves, and not justified via self-citation chains. No load-bearing step reduces to the result by construction; the derivation is self-contained against the chosen force fields.

Axiom & Free-Parameter Ledger

0 free parameters · 3 axioms · 0 invented entities

The central observations rest on the validity of three standard interatomic potentials chosen for the system; no new entities or fitted constants are introduced beyond the simulation setup itself.

axioms (3)
  • domain assumption Embedded atom model correctly captures metallic bonding among Al, Co, Cu, Fe, and Ni atoms.
    Explicitly stated as the model used for metal-metal interactions.
  • domain assumption Lennard-Jones potential correctly captures interactions between the metal atoms and the Si substrate.
    Explicitly stated as the model used for metal-Si interactions.
  • domain assumption Stillinger-Weber potential correctly captures interactions among silicon atoms in the substrate.
    Explicitly stated as the model used for Si-Si interactions.

pith-pipeline@v0.9.1-grok · 5730 in / 1457 out tokens · 32495 ms · 2026-06-26T19:49:56.104414+00:00 · methodology

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Reference graph

Works this paper leans on

19 extracted references · 16 canonical work pages

  1. [1]

    2nd Edition

    Murty BS, Yeh JW, Ranganathan S, Bhattacharjee PP (2019) High-Entropy Alloys. 2nd Edition. Elsevier

    2019

  2. [2]

    Springer

    Gao MC, Yeh J-W, Liaw PK, Zhang Y (2016) High-entropy alloys: fundamentals and applications. Springer

    2016

  3. [3]

    Miracle, O.N

    Miracle DB, Senkov ON (2017) A critical review of high entropy alloys and related concepts. Acta Mater 122:448–511 . https://doi.org/10.1016/j.actamat.2016.08.081

    work page doi:10.1016/j.actamat.2016.08.081 2017

  4. [4]

    Phys Met Metallogr 115:692–696

    Bashev VF, Kushnerov OI (2014) Structure and properties of high-entropy CoCrCuFeNiSn x alloys. Phys Met Metallogr 115:692–696 . https://doi.org/10.1016/j.jallcom.2016.04.064

    work page doi:10.1016/j.jallcom.2016.04.064 2014

  5. [5]

    Phys Met Metallogr 118:39–47

    Bashev VF, Kushnerov OI (2017) Structure and properties of cast and splat-quenched high-entropy Al–Cu–Fe–Ni–Si alloys. Phys Met Metallogr 118:39–47 . https://doi.org/10.1134/S0031918X16100033

    work page doi:10.1134/s0031918x16100033 2017

  6. [6]

    Trans IMF 80:154–156

    Gulivets AN, Zabludovsky VA, Shtapenko EP, Kushnerev AI, Dergachov MP, Baskevich AS (2002) Multilayer Compound Co-P Films with Controlled Magnetic Properties. Trans IMF 80:154–156 . https://doi.org/10.1080/00202967.2002.11871457

    work page doi:10.1080/00202967.2002.11871457 2002

  7. [7]

    Xie et al

    Xie L, Brault P, Thomann A-L, Bauchire J-M (2013) AlCoCrCuFeNi high entropy alloy cluster growth and annealing on silicon: A classical molecular dynamics simulation study. Appl Surf Sci 285:810–816 . https://doi.org/10.1016/j.apsusc.2013.08.133

    work page doi:10.1016/j.apsusc.2013.08.133 2013

  8. [8]

    Intermetallics 68:78–86

    Xie L, Brault P, Thomann A, Yang X, Zhang Y, Shang G (2016) Molecular dynamics simulation of Al–Co–Cr–Cu–Fe–Ni high entropy alloy thin film growth. Intermetallics 68:78–86 . https://doi.org/10.1016/j.intermet.2015.09.008

    work page doi:10.1016/j.intermet.2015.09.008 2016

  9. [9]

    Erratum: Basic principles of STT-MRAM cell operation in memory arrays (Journal of Physics D: Applied Physics (2013) 46 (074001)),

    Xie L, Brault P, Bauchire J-M, Thomann A-L, Bedra L (2014) Molecular dynamics simulations of clusters and thin film growth in the context of plasma sputtering deposition. J Phys D Appl Phys 47:224004 . https://doi.org/10.1088/0022- 3727/47/22/224004

    work page doi:10.1088/0022- 2014

  10. [10]

    Plimpton, Fast Parallel Algorithms for Short-Range Molecular Dynamics, J

    Plimpton S (1995) Fast Parallel Algorithms for Short-Range Molecular Dynamics. J Comput Phys 117:1–19 . https://doi.org/10.1006/jcph.1995.1039

    work page doi:10.1006/jcph.1995.1039 1995

  11. [11]

    Stukowski, Visualization and analysis of atomistic simulation data with OVITO–the Open Visualization Tool, Model

    Stukowski A (2010) Visualization and analysis of atomistic simulation data with OVITO–the Open Visualization Tool. Model Simul Mater Sci Eng 18:015012 . https://doi.org/10.1088/0965-0393/18/1/015012

    work page doi:10.1088/0965-0393/18/1/015012 2010

  12. [12]

    Mater Sci Reports 9:251–310

    Daw MS, Foiles SM, Baskes MI (1993) The embedded-atom method: a review of theory and applications. Mater Sci Reports 9:251–310 . https://doi.org/10.1016/0920- 2307(93)90001-U

    work page doi:10.1016/0920- 1993

  13. [13]

    Zhou XW, Johnson RA, Wadley HNG (2004) Misfit-energy-increasing dislocations in This is a preprint version of a book chapter published in Springer Proceedings in Physics 263, 2021, pp. 419-427. The Version of Record is available at: https://doi.org/10.1007/978-3-030-74741-1_28 vapor-deposited CoFe/NiFe multilayers. Phys Rev B 69:144113 . https://doi.org/1...

    work page doi:10.1007/978-3-030-74741-1_28 2004

  14. [14]

    Computer simulation of local order in condensed phases of silicon

    Stillinger FH, Weber TA (1985) Computer simulation of local order in condensed phases of silicon. Phys Rev B 31:5262–5271 . https://doi.org/10.1103/PhysRevB.31.5262

    work page doi:10.1103/physrevb.31.5262 1985

  15. [15]

    J Mater Sci Technol 35:1175–1183

    Liu C, Peng W, Jiang CS, Guo H, Tao J, Deng X, Chen Z (2019) Composition and phase structure dependence of mechanical and magnetic properties for AlCoCuFeNix high entropy alloys. J Mater Sci Technol 35:1175–1183 . https://doi.org/10.1016/j.jmst.2018.12.014

    work page doi:10.1016/j.jmst.2018.12.014 2019

  16. [16]

    Scr Mater 114:31–34

    Yu PF, Cheng H, Zhang LJ, Zhang H, Ma MZ, Li G, Liaw PK, Liu RP (2016) Nanotwin’s formation and growth in an AlCoCuFeNi high-entropy alloy. Scr Mater 114:31–34 . https://doi.org/10.1016/j.scriptamat.2015.11.032

    work page doi:10.1016/j.scriptamat.2015.11.032 2016

  17. [17]

    Mater Trans 46:2817–2829

    Takeuchi A, Inoue A (2005) Classification of Bulk Metallic Glasses by Atomic Size Difference, Heat of Mixing and Period of Constituent Elements and Its Application to Characterization of the Main Alloying Element. Mater Trans 46:2817–2829 . https://doi.org/10.2320/matertrans.46.2817

    work page doi:10.2320/matertrans.46.2817 2005

  18. [18]

    Oxford University Press, Oxford ; New York

    Li W-K, Zhou G, Mak TCW (2008) Advanced structural inorganic chemistry. Oxford University Press, Oxford ; New York

    2008

  19. [19]

    J Appl Phys 109:103505

    Guo S, Ng C, Lu J, Liu CT (2011) Effect of valence electron concentration on stability of fcc or bcc phase in high entropy alloys. J Appl Phys 109:103505 . https://doi.org/10.1063/1.3587228

    work page doi:10.1063/1.3587228 2011