Pith. sign in

REVIEW 3 major objections 6 minor 40 references

Hydrogen bond symmetrization in high-pressure ice clathrates

T0 review · 3 major / 6 minor · reviewed 2026-08-07 · deepseek-v4-flash

Challenge this review Re-run · record.json Download PDF Read on arXiv ↗ Review JSON

Pith's one-line read Hydrogen bonds in hydrogen-filled ice clathrates symmetrize at much lower pressure than in pure ice, through a continuous crossover.

desk verdict First look at hydrogen-bond symmetrization in hydrogen-filled ices, but the quantitative crossover pressures hinge on an ML potential extrapolation and a proton-ordered model. read the letter →

arxiv 2506.13169 v1 pith:5HJ3PKEI submitted 2025-06-16 cond-mat.mtrl-sci

Lorenzo Monacelli , Maria Rescigno , Alasdair Nicholls , Umbertoluca Ranieri , Simone Di Cataldo , Livia Eleonora Bove This is my paper · ORCID
classification cond-mat.mtrl-sci
keywords hydrogenbondsymmetrizationfillediceclathrateshydratequantumnucleareffectsSSCHARamanspectroscopyhighpressure
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

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

The reading

The paper sets out to establish that hydrogen bond symmetrization—the pressure-driven moment when a water molecule's two O–H bonds become equal—happens differently in hydrogen-filled ice clathrates than in pure ice. Using Raman spectroscopy backed by quantum atomistic simulations, the authors argue that in the C2 and C3 filled-ice phases of hydrogen hydrate, symmetrization occurs as a continuous crossover with no change in crystal symmetry, and at markedly lower pressures than in pure ice: around 24 GPa in C2 versus about 55 GPa in ice VII/VIII, and around 70 GPa in C3 once quantum fluctuations are included. The central insight is that the dense H2 guest molecules and the quantum motion of protons together control the symmetrization geometry, shortening the critical O–O distance in C3 and even shaping the spectroscopic fingerprint. If true, this means hydrogen-rich planetary ice layers and any compressed water–hydrogen mixture cannot be described with pure-ice phase boundaries.

What carries the argument

The analysis rests on two tools. The Stochastic Self-Consistent Harmonic Approximation (SSCHA) is a method that replaces the quantum ionic wavefunction with an optimized Gaussian density matrix, producing anharmonic phonons and an average structure under pressure; it is what lets the authors include zero-point motion and anharmonicity, and it was previously used to describe symmetrization in pure ice. The interatomic forces come from an equivariant neural-network potential trained on DFT data. The central diagnostic quantity is the order parameter $\Delta = d_{\mathrm{OH}} - d_{\mathrm{HO}}$, the difference between the covalent and hydrogen-bond O–H distances; plotting $\Delta$ against pressure reveals the continuous character of the crossover, while the distance of the structure to half- and fully-symmetrized configurations confirms that the transition is gradual even in the proton-ordered model.

What would settle it

A pressure-quenched or in-situ neutron or X-ray diffraction experiment on the C2 phase between 20 and 30 GPa that locates hydrogen positions would show either a smooth increase of $\Delta = d_{\mathrm{OH}} - d_{\mathrm{HO}}$ toward zero (confirming the crossover) or a jump-like discontinuity (refuting it). For C3, recomputing the static symmetrization with an interatomic potential explicitly benchmarked at 100–110 GPa would test whether the predicted 110 GPa value is physical or an extrapolation artifact.

Watch

Extended reading notes

Core claim

In both the C2 and C3 phases of hydrogen hydrate, hydrogen bond symmetrization proceeds as a smooth, continuous crossover rather than a sharp phase transition, and it takes place without any change in the overall crystal symmetry. In C2 the crossover appears near 24 GPa—roughly half the pressure of the ice VII–X transition—while in C3 it appears near 70 GPa with quantum fluctuations (110 GPa in static calculations). The two phases share the same expanded ice-Ic water sublattice, yet they symmetrize at different critical O–O distances: about 2.41 Å in C2 and pure ice, but about 2.39 Å in C3, because the denser H2 population suppresses the transverse quantum fluctuations of the protons. The paper therefore claims that guest–host interaction and nuclear quantum effects, not just lattice geometry, determine where and how symmetrization occurs.

Load-bearing premise

The results assume the machine-learned potential trained on DFT data from 5–80 GPa stays accurate at the predicted crossover pressures, including the static C3 value of 110 GPa that lies outside the training range, and that the proton-ordered ice sublattice used in the simulations faithfully represents the real phases.

Editorial extensions

If this is right

  • In the C2 phase the OH stretching mode softens, broadens, and disappears near 24 GPa, giving a clear Raman signature of the crossover even though no ice-X-like T2g mode appears.
  • Deuterating the water framework shifts the C2 crossover up by about 5 GPa, showing that nuclear quantum motion lowers the symmetrization pressure.
  • In C3 the symmetrization-related stretching mode is so strongly mixed with low-frequency translational modes that it is spectroscopically silent; only simulations reveal the crossover near 70 GPa (quantum) or 110 GPa (static).
  • The critical O–O distance is not universal: C3 symmetrizes at 2.39 Å, about 0.02 Å shorter than C2 and pure ice, because dense H2 guests suppress transverse proton fluctuations.
  • Static calculations fail to symmetrize C2 at all in the studied range, implying that quantum fluctuations are essential for the low-pressure crossover.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • If the continuous-crossover picture holds, the notion of a sharp ice VII→X-type transition should be replaced by a crossover line in the C2/C3 region of the water–hydrogen phase diagram; the exact boundary may then depend on temperature and isotope in a way that a single transition pressure cannot capture.
  • A direct test would be a DFT calculation of the C3 static transition near 110 GPa, or an experimental compression of C3 beyond 90 GPa with a probe sensitive to proton positions, both of which would check whether the predicted quantum 70 GPa value is robust.
  • The same protocol could be applied to other filled ices, such as methane hydrates or salty ice, to ask whether guest-induced suppression of transverse proton fluctuations generalizes the C3 result.
  • A testable prediction is that the proton's inelastic neutron scattering spectrum in C3 should show reduced transverse librational amplitude compared to C2 at the same O–O distance.
Share X Bluesky LinkedIn Reddit HN

Signed reviews

No signed human review yet.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

3 major / 6 minor

Summary. The manuscript reports a combined experimental and computational study of hydrogen bond symmetrization in the filled-ice hydrogen hydrate phases C2 and C3. Using Raman spectroscopy and SSCHA simulations driven by a NequIP machine-learned potential, the authors find that the OH stretching mode in C2 softens and disappears, and that the quantum-renormalized OH bond lengths undergo a continuous crossover around 24 GPa in C2 and around 70 GPa (quantum) versus 110 GPa (static) in C3. They argue that symmetrization occurs without a change in crystal symmetry and that the critical O–O distance is approximately 2.41 Å for C2 and pure ice, but 2.39 Å for C3, reflecting suppression of transverse proton fluctuations by the dense H2 sublattice.

Significance. If the quantitative predictions are correct, the work significantly advances the field: it extends hydrogen-bond symmetrization studies to hydrogen-filled ices, demonstrates a large isotope/quantum effect, and identifies guest–host interactions as a control parameter that shifts the critical geometry. The combination of state-of-the-art anharmonic quantum simulations with experimental Raman data, including the isotopic comparison, is a strength. The C3 prediction (110→70 GPa quantum shift) and the critical O–O distance ordering are falsifiable. However, the ML-potential extrapolation beyond 80 GPa and the use of a proton-ordered water sublattice leave the quantitative central claims in need of further validation.

major comments (3)
  1. [Appendix: Numerical Methods] The NequIP potential is trained on DFT data from 5–40 GPa (C2) and 40–80 GPa (C3), with direct DFT benchmarks reported only at 20 and 30 GPa. The static C3 symmetrization pressure of ~110 GPa is therefore an extrapolation 30 GPa above the training range, and the quantum C3 result at ~70 GPa sits at the upper edge of that range. Since the central quantitative claims for C3 (110 GPa static, 70 GPa quantum, and the 2.39 Å critical O–O distance) are outputs of this potential, please add direct DFT validation at and around 70 and 110 GPa—for example, the OH bond length, the proton potential profile along the hydrogen bond, and the SSCHA renormalized phonons at those pressures—or provide a systematic uncertainty estimate for the ML potential at those compressions.
  2. [II, paragraph beginning 'To shed light on the crossover character...'] The claim that symmetrization is a continuous crossover with no change in overall crystal symmetry is derived from a proton-ordered model of the water sublattice ('as in ice VIII and XI'). The actual C2 and C3 phases are based on an expanded ice Ic framework, whose proton disorder is not represented in the simulations. Proton disorder could alter the order parameter, broaden or smear the crossover, and affect the interpretation of 'no overall symmetry change.' Please test at least one disordered supercell or explicitly discuss the expected effect of proton disorder on the crossover character and on the symmetry statement in the abstract.
  3. [II, Fig. 3 and Conclusions] The experimental Raman data for C2 are confined to pressures below about 12–17 GPa, where the hydrate OH mode becomes obscured by the diamond signal and broadening; no experimental observable tracks the mode to zero frequency or confirms the crossover at ~24 GPa. The conclusion in Section III that 'Raman spectroscopy ... reveals a clear softening and eventual disappearance of the OH stretching mode, consistent with a continuous symmetrization process occurring around 24 GPa' overstates the experimental reach. Please rephrase to attribute the 24 GPa crossover and its continuity to the simulations, and to state explicitly that the experiment validates only the pre-crossover redshift.
minor comments (6)
  1. [Figure 1 caption] The caption states that the top and bottom right panels correspond to D2O-D2, while the main text says the top and bottom left panels are H2:D2O; please correct this inconsistency.
  2. [Figure 2 caption] The caption uses 'SCHA' but the method abbreviation used elsewhere is 'SSCHA'; please make this uniform.
  3. [Figure 3 caption] The word 'losange' appears in the caption; this should be 'diamonds' in English.
  4. [Figure 5 caption] Please define the plotted quantity explicitly, including the order parameter Δ and the meaning of the third-root-of-volume normalization; the current caption is difficult to parse.
  5. [III, Conclusions] The phrase 'Raman spectroscopy ... reveals a clear softening and eventual disappearance' should be qualified, as the experimental Raman data do not extend through the disappearance; the simulations provide the disappearance signature.
  6. [III, text near Fig. 3] Please add a sentence clarifying that the 270 cm⁻¹ rigid frequency shift is applied only to improve the frequency comparison and does not affect the predicted crossover pressure or the O–O distance analysis.

Circularity Check

0 steps flagged · score 0.0 of 10

No circularity found: the crossover pressures are outputs of DFT-trained SSCHA simulations, not fits to the experimental transition.

full rationale

The derivation chain is not circular. The quantitative crossover pressures (C2 near 24 GPa, C3 static near 110 GPa vs quantum near 70 GPa) are outputs of SSCHA free-energy minimizations using a NequIP potential trained on DFT data from ref. [11]; the only fitted quantity is a rigid 270 cm-1 Raman frequency shift, which does not enter the pressure determination. The experimental Raman data validate the pre-crossover redshift but do not pin the crossover; the crossover pressure is therefore not fitted to the experimental transition. The comparison with pure ice at 55 GPa and at a critical O-O distance of 2.41 Å uses the previously published SSCHA calculation of ref. [5], which is an independent calculation, not an input to the present fit. Training on DFT configurations from ref. [11] is a standard first-principles data source and does not define the target observable. The main limitation—the C3 static value at 110 GPa lies outside the 40–80 GPa training window, with direct DFT benchmarks only at 20 and 30 GPa—is an extrapolation risk and a correctness concern, not a circular reduction. Likewise, the proton-ordered model is an explicitly stated approximation; the continuous-crossover characterization is demonstrated within that model, not claimed to be definitionally forced. No equation in the paper reduces a prediction to a fitted parameter or to a self-citation chain.

Assumptions & free parameters 1 free parameters · 4 assumptions · 0 invented entities

The load-bearing assumptions are all about the simulation pipeline: the ML potential's accuracy including extrapolation, the proton-ordered structural model, and the SSCHA Gaussian ansatz. There is exactly one fitted numerical constant, the 270 cm-1 shift, and no invented physical entities.

free parameters (1)
  • Rigid Raman frequency shift = 270 cm-1
    Applied to all simulated OH/OD stretching frequencies to correct the known semi-local DFT underestimation, cited as ref. 37. It does not enter the transition-pressure calculation but is a fitted constant used in the experimental comparison.
assumptions (4)
  • domain assumption SSCHA Gaussian ansatz accurately describes quantum nuclear fluctuations in C2/C3 hydrogen hydrates.
    The method is established for ice VII/X, ref. 5, but its accuracy for the H2-loaded phases is not separately validated; the H2 rotations are explicitly stated to be outside the SSCHA framework.
  • domain assumption The proton-ordered water sublattice with two inequivalent H2O molecules is representative of the real C2/C3 phases.
    Simulations use a proton-ordered model as in ice VIII/XI; the paper does not test proton disorder, yet the continuous-crossover claim is based on this model.
  • domain assumption The NequIP ML potential reproduces DFT energies and forces over 5-80 GPa and extrapolates reliably to 110 GPa for the static C3 calculation.
    Training data are sampled from 5-40 GPa for C2 and 40-80 GPa for C3; the direct DFT benchmark is only at 20 and 30 GPa, so the static C3 pressure of 110 GPa is an extrapolation.
  • domain assumption Raman mode softening and disappearance, together with the absence of a T2g mode, are reliable proxies for inferring hydrogen-bond symmetrization and the crossover character.
    The paper relies on the known Raman signature from ice X but states that no T2g mode appears in C2, so the inference is indirect and model-dependent.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Hydrogen bond symmetrization in high-pressure ice clathrates." pith.science (2026). https://pith.science/paper/5HJ3PKEI

@misc{pith2026250613169,
  author       = {Pith},
  title        = {Pith review of: Hydrogen bond symmetrization in high-pressure ice clathrates},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/5HJ3PKEI}},
  note         = {Machine review of arXiv:2506.13169}
}
read the original abstract

Hydrogen bond symmetrization is a fundamental pressure-induced transformation in which the distinction between donor and acceptor sites vanishes, resulting in a symmetric hydrogen-bond network. While extensively studied in pure ice, most notably during the ice VII to ice X transition, this phenomenon remains less well characterized in hydrogen hydrates. In this work, we investigate hydrogen bond symmetrization in the high-pressure phases of hydrogen hydrate (H2-H2O and H2-D2O) through a combined approach of Raman spectroscopy and first-principles quantum atomistic simulations. We focus on the C2 and C3 filled-ice phases, using both hydrogenated and deuterated water frameworks. Our results reveal that quantum fluctuations and the interaction between the encaged H2 molecules and the host lattice play a crucial role in driving the symmetrization process. Remarkably, we find that in both C2 and C3 phases, hydrogen bond symmetrization occurs via a continuous crossover at significantly lower pressures than in pure ice, without any change in the overall crystal symmetry. These findings provide new insight into the quantum-driven mechanisms of bond symmetrization in complex hydrogen-bonded systems under extreme conditions.

Figures

Figures reproduced from arXiv: 2506.13169 by the authors.

Figure 1
Figure 1. FIG. 1. Raman spectra measured in the D [PITH_FULL_IMAGE:figures/full_fig_p003_1.png] view at source ↗
Figure 2
Figure 2. FIG. 2. Anharmonic Raman spectrum computed within the SCHA in the H [PITH_FULL_IMAGE:figures/full_fig_p003_2.png] view at source ↗
Figure 4
Figure 4. FIG. 4. OH bonds as a function of pressure. Comparison [PITH_FULL_IMAGE:figures/full_fig_p004_4.png] view at source ↗
Figures from the paper (2 more)
Figure 5
Figure 5. Figure 5: FIG. 5. Distance of the ice clathrate to the configurations [PITH_FULL_IMAGE:figures/full_fig_p004_5.png]
Figure 6
Figure 6. Figure 6: FIG. 6 [PITH_FULL_IMAGE:figures/full_fig_p005_6.png]

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

40 extracted references · 39 canonical work pages

  1. [1]

    Infrared absorption study of the hydrogen-bond sym- metrization in ice to 110 gpa,

    K. Aoki, H. Yamawaki, M. Sakashita, and H. Fujihisa, “Infrared absorption study of the hydrogen-bond sym- metrization in ice to 110 gpa,”Phys. Rev. B, vol. 54, pp. 15673–15677, Dec 1996

    work page 1996

  2. [2]

    Compression of ice to 210 gigapascals: Infrared evidence for a symmetric hydrogen- bonded phase,

    A. F. Goncharov, V. V. Struzhkin, M. S. Somayazulu, R. J. Hemley, and H. K. Mao, “Compression of ice to 210 gigapascals: Infrared evidence for a symmetric hydrogen- bonded phase,”Science, vol. 273, no. 5272, pp. 218–220, 1996

    work page 1996

  3. [3]

    Raman Scattering and X-ray Diffraction of Ice in the Megabar Range. Occurrence of a Symmetric Disordered Solid above 62 GPa,

    P. Pruzan, E. Wolanin, M. Gauthier, J. C. Chervin, B. Canny, D. H¨ ausermann, and M. Hanfland, “Raman Scattering and X-ray Diffraction of Ice in the Megabar Range. Occurrence of a Symmetric Disordered Solid above 62 GPa,”The Journal of Physical Chemistry B, vol. 101, pp. 6230–6233, Aug. 1997. Publisher: Ameri- can Chemical Society

    work page 1997

  4. [4]

    Hydrogen bond sym- metrisation in D2O ice observed by neutron diffraction,

    K. Komatsu, T. Hattori, S. Klotz, S. Machida, K. Ya- mashita, H. Ito, H. Kobayashi, T. Irifune, T. Shinmei, A. Sano-Furukawa, and H. Kagi, “Hydrogen bond sym- metrisation in D2O ice observed by neutron diffraction,” Nature Communications, vol. 15, p. 5100, June 2024

    work page 2024

  5. [5]

    Quantum effects in H-bond symmetriza- tion and in thermodynamic properties of high pressure ice,

    M. Cherubini, L. Monacelli, B. Yang, R. Car, M. Casula, and F. Mauri, “Quantum effects in H-bond symmetriza- tion and in thermodynamic properties of high pressure ice,”Physical Review B, vol. 110, p. 014112, July 2024. Publisher: American Physical Society

    work page 2024

  6. [6]

    Effect of salt on the h-bond symmetrization in ice,

    L. E. Bove, R. Gaal, Z. Raza, A.-A. Ludl, S. Klotz, A. M. Saitta, A. F. Goncharov, and P. Gillet, “Effect of salt on the h-bond symmetrization in ice,”Proceedings of the National Academy of Sciences, vol. 112, pp. 8216–8220, 7 2015

    work page 2015

  7. [7]

    Quantum versus classical pro- tons in pure and salty ice under pressure,

    Y. Bronstein, P. Depondt, L. E. Bove, R. Gaal, A. M. Saitta, and F. Finocchi, “Quantum versus classical pro- tons in pure and salty ice under pressure,”Physical Re- view B, vol. 93, p. 024104, 1 2016

    work page 2016

  8. [8]

    Orientational Ordering, Locking-in, and Distortion of CH4 Molecules in Methane Hydrate III under High Pres- sure,

    S. Schaack, U. Ranieri, P. Depondt, R. Gaal, W. F. Kuhs, A. Falenty, P. Gillet, F. Finocchi, and L. E. Bove, “Orientational Ordering, Locking-in, and Distortion of CH4 Molecules in Methane Hydrate III under High Pres- sure,”The Journal of Physical Chemistry C, vol. 122, pp. 11159–11166, May 2018. Publisher: American Chem- ical Society

    work page 2018

Show all 40 references
  1. [9]

    Observation of methane filled hexagonal ice stable up to 150 gpa,

    S. Schaack, U. Ranieri, P. Depondt, R. Gaal, W. F. Kuhs, P. Gillet, F. Finocchi, and L. E. Bove, “Observation of methane filled hexagonal ice stable up to 150 gpa,”Pro- ceedings of the National Academy of Sciences, vol. 116, no. 33, pp. 16204–16209, 2019

    2019

  2. [10]

    Structural independence of hydrogen- bond symmetrisation dynamics at extreme pressure con- ditions,

    T. Meier, F. Trybel, S. Khandarkhaeva, D. Laniel, T. Ishii, A. Aslandukova, N. Dubrovinskaia, and L. Dubrovinsky, “Structural independence of hydrogen- bond symmetrisation dynamics at extreme pressure con- ditions,”Nature Communications, vol. 13, no. 1, p. 3042, 2022

    2022

  3. [11]

    Observation of the most H2-dense filled ice under high pressure,

    U. Ranieri, S. Di Cataldo, M. Rescigno, L. Monacelli, R. Gaal, M. Santoro, L. Andriambariarijaona, P. Parisi- ades, C. De Michele, and L. E. Bove, “Observation of the most H2-dense filled ice under high pressure,”Pro- ceedings of the National Academy of Sciences, vol. 120, p. ...

    2023

  4. [12]

    Giant splitting of the hydrogen rota- tional eigenenergies in the c2 filled ice,

    S. Di Cataldo, M. Rescigno, L. Monacelli, U. Ranieri, R. Gaal, S. Klotz, J. Ollivier, M. M. Koza, C. De Michele, and L. E. Bove, “Giant splitting of the hydrogen rota- tional eigenenergies in the c2 filled ice,”Phys. Rev. Lett., vol. 133, p. 236101, Dec 2024

    2024

  5. [13]

    Struc- ture and dynamics of hydrogen molecules in the novel clathrate hydrate by high pressure neutron diffraction,

    K. A. Lokshin, Y. Zhao, D. He, W. L. Mao, H.-K. Mao, R. J. Hemley, M. V. Lobanov, and M. Greenblatt, “Struc- ture and dynamics of hydrogen molecules in the novel clathrate hydrate by high pressure neutron diffraction,” Physical Review Letters, vol. 93, p. 125503, 9 2004

    2004

  6. [14]

    Quantum Dynamics of H2 and D2 Confined in Hydrate Structures as a Function of Pressure and Tem- perature,

    U. Ranieri, M. M. Koza, W. F. Kuhs, R. Gaal, S. Klotz, A. Falenty, D. Wallacher, J. Ollivier, P. Gillet, and L. E. Bove, “Quantum Dynamics of H2 and D2 Confined in Hydrate Structures as a Function of Pressure and Tem- perature,”The Journal of Physical Chemistry C, vol. 123, pp...

    1903

  7. [15]

    Large-cage occupation and quantum dynamics of hydro- gen molecules in sII clathrate hydrates,

    U. Ranieri, L. del Rosso, L. E. Bove, M. Celli, D. Colog- nesi, R. Gaal, T. C. Hansen, M. M. Koza, and L. Ulivi, “Large-cage occupation and quantum dynamics of hydro- gen molecules in sII clathrate hydrates,”The Journal of Chemical Physics, vol. 160, p. 164706, Apr. 2024

    2024

  8. [16]

    A chiral gas–hydrate structure common to the carbon dioxide–water and hydrogen–water systems,

    D. M. Amos, M.-E. Donnelly, P. Teeratchanan, C. L. Bull, A. Falenty, W. F. Kuhs, A. Hermann, and J. S. Loveday, “A chiral gas–hydrate structure common to the carbon dioxide–water and hydrogen–water systems,”The Journal of Physical Chemistry Letters, vol. 8, pp. 4295– 4299, 9 2017

    2017

  9. [17]

    Hydrogen-stuffed, quartz-like water ice,

    T. A. Strobel, M. Somayazulu, S. V. Sinogeikin, P. Dera, and R. J. Hemley, “Hydrogen-stuffed, quartz-like water ice,”Journal of the American Chemical Society, vol. 138, no. 42, pp. 13786–13789, 2016. PMID: 27540626

    2016

  10. [18]

    Refined structure of metastable ice xvii from neutron diffraction measurements,

    L. del Rosso, F. Grazzi, M. Celli, D. Colognesi, V. Garcia- Sakai, and L. Ulivi, “Refined structure of metastable ice xvii from neutron diffraction measurements,”The Jour- nal of Physical Chemistry C, vol. 120, no. 47, pp. 26955– 26959, 2016

    2016

  11. [19]

    T–p–x phase diagram of the water–hydrogen system at pressures up to 10 kbar,

    M. Kuzovnikov and M. Tkacz, “T–p–x phase diagram of the water–hydrogen system at pressures up to 10 kbar,” The Journal of Physical Chemistry C, vol. 123, no. 6, pp. 3696–3702, 2019

    2019

  12. [20]

    Novel h2-h2o clathrates at high pressures,

    W. L. Vos, L. W. Finger, R. J. Hemley, and H.-k. Mao, “Novel h2-h2o clathrates at high pressures,”Phys. Rev. Lett., vol. 71, pp. 3150–3153, Nov 1993

    1993

  13. [21]

    Exploring high-pressure transformations in low-z (h2, ne) hydrates at low temperatures,

    P. H. B. Brant Carvalho, A. Mace, I. M. Nangoi, A. A. Leit˜ ao, C. A. Tulk, J. J. Molaison, O. Anders- son, A. P. Lyubartsev, and U. H¨ aussermann, “Exploring high-pressure transformations in low-z (h2, ne) hydrates at low temperatures,”Crystals, vol. 12, no. 1, 2022

    2022

  14. [22]

    Hydrogen hydrates under extreme con- ditions: Insights into high-pressure phases and implica- tions for planetary interiors,

    L. Andriambariarijaona, T. Poreba, S. D. Cataldo, R. Gaal, U. Ranieri, M. Santoro, T. Hansen, G. Tobie, and L. E. Bove, “Hydrogen hydrates under extreme con- ditions: Insights into high-pressure phases and implica- tions for planetary interiors,”Physical Review B, in press

  15. [23]

    Ice Ic without stacking disorder by evacuating hydrogen from hydrogen hydrate,

    K. Komatsu, S. Machida, F. Noritake, T. Hattori, A. Sano-Furukawa, R. Yamane, K. Yamashita, and H. Kagi, “Ice Ic without stacking disorder by evacuating hydrogen from hydrogen hydrate,”Nature Communica- tions, vol. 11, p. 464, Feb. 2020

    2020

  16. [24]

    Geophysical Characterization of the Interi- ors of Ganymede, Callisto and Europa by ESA’s JUpiter ICy moons Explorer,

    T. Van Hoolst, G. Tobie, C. Vallat, N. Altobelli, L. Bruzzone, H. Cao, D. Dirkx, A. Genova, H. Huss- mann, L. Iess, J. Kimura, K. Khurana, A. Lucchetti, 8 G. Mitri, W. Moore, J. Saur, A. Stark, A. Vor- burger, M. Wieczorek, A. Aboudan, J. Bergman, F. Bo- volo, D. Breuer, P. Ca...

    2024

  17. [25]

    Reassigning hydrogen-bond centering in dense ice,

    M. Benoit, A. H. Romero, and D. Marx, “Reassigning hydrogen-bond centering in dense ice,”Physical Review Letters, vol. 89, p. 145501, 9 2002

    2002

  18. [26]

    Proton dynamics and the phase diagram of dense water ice.,

    C. R. Hernandez JA, “Proton dynamics and the phase diagram of dense water ice.,”The Journal of Chemical Physics, vol. 148, p. 214501, June 2018. Publisher: Amer- ican Chemical Society

    2018

  19. [27]

    The stochastic self-consistent harmonic approximation: calculating vibrational proper- ties of materials with full quantum and anharmonic ef- fects,

    L. Monacelli, R. Bianco, M. Cherubini, M. Calandra, I. Errea, and F. Mauri, “The stochastic self-consistent harmonic approximation: calculating vibrational proper- ties of materials with full quantum and anharmonic ef- fects,”Journal of Physics: Condensed Matter, vol. 33, p. 3...

    2021

  20. [28]

    Fast prediction of anharmonic vibrational spectra for complex organic molecules,

    M. Miotto and L. Monacelli, “Fast prediction of anharmonic vibrational spectra for complex organic molecules,”npj Computational Materials, vol. 10, pp. 1– 9, Oct. 2024. Publisher: Nature Publishing Group

    2024

  21. [29]

    Black metal hydrogen above 360 GPa driven by proton quantum fluctuations,

    L. Monacelli, I. Errea, M. Calandra, and F. Mauri, “Black metal hydrogen above 360 GPa driven by proton quantum fluctuations,”Nature Physics, vol. 17, pp. 63– 67, Sept. 2020. Publisher: Springer Science and Business Media LLC

    2020

  22. [30]

    Quantum phase diagram of high-pressure hy- drogen,

    L. Monacelli, M. Casula, K. Nakano, S. Sorella, and F. Mauri, “Quantum phase diagram of high-pressure hy- drogen,”Nature Physics, vol. 19, pp. 845–850, June 2023. Publisher: Nature Publishing Group

    2023

  23. [31]

    E(3)-equivariant graph neural networks for data-efficient and accurate interatomic potentials,

    S. Batzner, A. Musaelian, L. Sun, M. Geiger, J. P. Mailoa, M. Kornbluth, N. Molinari, T. E. Smidt, and B. Kozinsky, “E(3)-equivariant graph neural networks for data-efficient and accurate interatomic potentials,”Na- ture Communications, vol. 13, p. 2453, May 2022. Num- ber: 1 ...

    2022

  24. [32]

    Beyond Gaus- sian fluctuations of quantum anharmonic nuclei,

    A. Siciliano, L. Monacelli, and F. Mauri, “Beyond Gaus- sian fluctuations of quantum anharmonic nuclei,”Physi- cal Review B, vol. 110, p. 134111, Oct. 2024. Publisher: American Physical Society

    2024

  25. [33]

    Beyond Gaus- sian fluctuations of quantum anharmonic nuclei: The case of rotational degrees of freedom,

    A. Siciliano, L. Monacelli, and F. Mauri, “Beyond Gaus- sian fluctuations of quantum anharmonic nuclei: The case of rotational degrees of freedom,”Physical Review B, vol. 110, p. 144101, Oct. 2024. Publisher: American Physical Society

    2024

  26. [34]

    Bianco, I

    R. Bianco, I. Errea, L. Paulatto, M. Calandra, and F. Mauri, “Second-order structural phase transitions, free energy curvature, and temperature-dependent an- harmonic phonons in the self-consistent harmonic ap- proximation: Theory and stochastic implementation,” Physical Revie...

    2017

  27. [35]

    Time-dependent self- consistent harmonic approximation: Anharmonic nu- clear quantum dynamics and time correlation functions,

    L. Monacelli and F. Mauri, “Time-dependent self- consistent harmonic approximation: Anharmonic nu- clear quantum dynamics and time correlation functions,” Physical Review B, vol. 103, p. 104305, Mar. 2021. Pub- lisher: American Physical Society (APS)

    2021

  28. [36]

    Wigner Gaussian dynamics: Simulating the anharmonic and quantum ionic motion,

    A. Siciliano, L. Monacelli, G. Caldarelli, and F. Mauri, “Wigner Gaussian dynamics: Simulating the anharmonic and quantum ionic motion,”Physical Review B, vol. 107, p. 174307, May 2023. Publisher: American Physical So- ciety

    2023

  29. [37]

    The mi- croscopic origin of the anomalous isotopic properties of ice relies on the strong quantum anharmonic regime of atomic vibration,

    M. Cherubini, L. Monacelli, and F. Mauri, “The mi- croscopic origin of the anomalous isotopic properties of ice relies on the strong quantum anharmonic regime of atomic vibration,”Journal of Chemical Physics, vol. 155, p. 184502, Nov. 2021. Publisher: AIP Publishing

    2021

  30. [38]

    Simulating anharmonic crystals: Lights and shadows of first-principles approaches,

    L. Monacelli, “Simulating anharmonic crystals: Lights and shadows of first-principles approaches,”ArXiV, vol. 2407.03090, July 2024. arXiv:2407.03090

    2024 arXiv

  31. [39]

    Pres- sure and stress tensor of complex anharmonic crystals within the stochastic self-consistent harmonic approxi- mation,

    L. Monacelli, I. Errea, M. Calandra, and F. Mauri, “Pres- sure and stress tensor of complex anharmonic crystals within the stochastic self-consistent harmonic approxi- mation,”Physical Review B, vol. 98, p. 024106, July

  32. [2018]

    Publisher: American Physical Society (APS)

Pith tools

Reviewed August 7, 2026 · model on record in the stance chip above.