Pith. sign in

REVIEW 4 major objections 5 minor 53 references

Evidences for local non-centrosymmetricity and strong phonon anomaly in EuCu2As2: A Raman spectroscopy and lattice dynamics study

T0 review · 4 major / 5 minor · reviewed 2026-08-10 · deepseek-v4-flash

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

Pith's one-line read This paper argues that EuCu2As2 realizes the locally non-centrosymmetric P4/nmm structure instead of the accepted I4/mmm structure, and that anomalous hardening of the strongest phonon mode below 165 K signals a subtle electronic density…

desk verdict First Raman study of EuCu2As2 makes a plausible but not airtight case for P4/nmm over I4/mmm, and reports a real 165 K phonon anomaly whose density-wave origin is speculative. read the letter →

arxiv 2501.05296 v1 pith:YDJQ7MIB submitted 2025-01-09 cond-mat.str-el

Debasmita Swain , Mainak Dey Sarkar , Andrzej Ptok , G. Vaitheeswaran , Anushree Roy , Sitikantha D Das This is my paper · ORCID
classification cond-mat.str-el PACS 78.30.-j63.20.-e71.45.Lr
keywords EuCu2As2RamanspectroscopyP4/nmmstructureI4/mmmphononanomalylatticedynamicschargedensitywave122pnictides
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

This paper argues that the copper pnictide EuCu2As2 has been assigned the wrong crystal structure since its discovery: Raman spectroscopy shows seven well-defined optical phonon peaks above 100 $cm^{-1}$, whereas the accepted ThCr2Si2-type I4/mmm structure admits only four Raman-active modes, and density-functional lattice dynamics find I4/mmm dynamically unstable while the locally non-centrosymmetric CaBe2Ge2-type P4/nmm structure is stable and reproduces the measured frequencies. The authors take this as strong evidence that EuCu2As2 actually realizes P4/nmm, a structure rare among the copper-arsenide 122 family. They further report that the strongest mode, the A1g phonon near 232 $cm^{-1}$, hardens below about 165 K far beyond the fitted anharmonic decay, with smaller anomalies in four other modes and a slight deviation in the $Eu^{{2+}}$ Curie–Weiss susceptibility. They interpret this as a strong signature of a subtle electronic density wave instability that couples to out-of-plane vibrations of the interlayer Cu(2) and As(1) atoms, while conceding that the usual CDW fingerprints (amplitude, zone-folded, or two-phonon modes) have not been resolved. If correct, the work puts EuCu2As2 in a short list of 122 pnictides with local inversion-symmetry breaking and points to a rare density-wave phase in this family.

What carries the argument

The argument is carried by three coupled tools. Mode counting: for I4/mmm the Γ-point optical modes decompose into A1g + 2A2u + B1g + 2Eu + 2Eg, giving four Raman-active bands (A1g, B1g, and two Eg doublets), whereas P4/nmm gives ten Raman-active bands (3A1g + 2B1g + 5Eg); observing seven distinct peaks is therefore a symmetry-level contradiction of the accepted structure. Lattice dynamics: DFT+U (PBEsol, U = 7 eV on the Eu 4f states) phonon dispersions computed by the supercell force-constant method yield imaginary soft modes for I4/mmm — the hallmark of a dynamically unstable structure — and a purely real, stable spectrum for P4/nmm whose frequencies near the Γ point track the measured modes. Anharmonic model: the temperature dependence of each mode is fit to the Balkanski–Wallis–Haro three- and four-phonon decay formula between 165 K and 300 K and extrapolated down; the area between the extrapolated curve and the data below 165 K quantifies the anomaly, which is largest for the out-of-plane A1g mode and decreases monotonically from P7 to P1, tying the instability to the interlayer Cu(2)–As(1) vibrations of the A1g mode.

What would settle it

Refining single-crystal X-ray or neutron diffraction of EuCu2As2 and hunting specifically for weak reflections with odd (hkl) index sums — forbidden by I4/mmm but allowed by P4/nmm — would decide the structure question directly, as would repeating the phonon calculation over a range of U values and functionals to see whether the I4/mmm imaginary modes survive the choice of method. For the 165 K anomaly, resolving the CDW fingerprints the paper could not see — an amplitude mode, zone-folded modes, or two-phonon features appearing below 165 K — would confirm the density wave, while a bulk probe (specific heat, resistivity, thermal expansion) showing no feature at 165 K would weigh against the electronic-instability interpretation.

Watch

Extended reading notes

Core claim

Stated on the paper's own terms, the discovery is that the accepted I4/mmm picture of EuCu2As2 is wrong and that the consequences are observable: seven first-order Raman bands — at approximately 115, 126, 150, 170, 201, 224, and 235 $cm^{-1}$ — exceed what I4/mmm symmetry permits and match, in count, symmetry labels (Eg, B1g, A1g, B1g, Eg, Eg, A1g), and frequency, the Γ-point phonons of the locally non-centrosymmetric P4/nmm structure computed with DFT+U. The same calculation shows I4/mmm to be dynamically unstable, with imaginary soft modes from in-plane Cu and As vibrations, and P4/nmm to be stable, with a phonon spectrum whose highest modes are dominated by Cu and As motion while Eu vibrations sit below about 150 $cm^{-1}$. On cooling, the A1g mode at ~232 $cm^{-1}$ departs from the anharmonic (three- and four-phonon decay) curve below 165 K, abruptly hardening while narrowing faster than the anharmonic fit; four other modes show smaller versions of the same deviation. The authors propose that an electronic density wave instability, analogous to the CDW states seen in Raman studies of transition-metal dichalcogenides and kagome metals and in the P4/nmm 122 compound SrPt2As2, gaps part of the Fermi surface and stiffens the phonons, particularly the out-of-plane A1g vibration of the interlayer Cu(2) and As(1) atoms. They explicitly stop short of claiming conclusive proof: no amplitude modes, zone-folded modes, or two-phonon features were observed, and more detailed studies are called for.

Load-bearing premise

The structural conclusion rests on the assumption that the DFT+U phonon calculation (PBEsol with U = 7 eV on the Eu 4f states) correctly predicts I4/mmm to be dynamically unstable, and that the seven Raman bands are intrinsic first-order modes of bulk EuCu2As2 rather than a near-surface artifact; the authors themselves note that Raman probes only the surface and that a P4/nmm surface sitting on an I4/mmm bulk cannot be excluded from experiment alone, and they report no test of how the result depends on the chosen U value or exchange-correlation functional.

Editorial extensions

If this is right

  • EuCu2As2 would join SrPt2As2 and CeRh2As2 as a 122 pnictide realizing the locally non-centrosymmetric CaBe2Ge2-type P4/nmm structure, breaking the rule that copper-arsenide 122 compounds take the ThCr2Si2-type I4/mmm form.
  • The seven-peak Raman pattern, anchored by the intense ~232 cm^-1 A1g mode, becomes a quick experimental fingerprint for P4/nmm order in other copper-based 122 compounds.
  • Below 165 K, the hardening of the A1g mode and its accelerated linewidth narrowing imply a partial gap on the Fermi surface and a reduced electron–phonon coupling — the behavior expected of a subtle charge density wave whose amplitude mode has so far escaped detection.
  • The near-degeneracy of the computed magnetic ground states and the small non-compensated moments induced on Cu(2) and As(1) near the Eu layer suggest that pressure or magnetic field could tune between density-wave and magnetic orders, as already seen for the Eu spin arrangement.

Reading between the lines

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

  • If the P4/nmm assignment survives bulk-sensitive probes, then the 'collapsed tetragonal' picture of Cu-based 122 pnictides may have been describing a dynamical average: with I4/mmm phonons carrying imaginary soft modes, the accepted structure could be an unstable parent from which a locally non-centrosymmetric ground state emerges.
  • A targeted bulk probe — specific heat, resistivity, or thermal expansion across 165 K — is the cheapest test of the density-wave reading: a small anomaly located at 165 K would strengthen it, while a clean null result would push the hardening toward a magnetic-fluctuation origin tied to the Eu sublattice.
  • Because the experiment used a polycrystalline sample and a single 532 nm laser line, repeating the measurements on single crystals with polarization analysis and with different laser wavelengths (varying penetration depth) could confirm that all seven modes are bulk first-order Raman phonons and fix their symmetries unambiguously.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

4 major / 5 minor

Summary. The paper reports Raman spectra, powder XRD, magnetic susceptibility, and DFT-based lattice dynamics for EuCu2As2. The central claim is that the compound does not adopt the accepted ThCr2Si2-type I4/mmm structure but instead realizes the CaBe2Ge2-type P4/nmm structure: seven Raman peaks are observed above 100 cm−1, which is more than the four Raman-active modes expected for I4/mmm, and DFT phonon calculations find an imaginary mode for I4/mmm while P4/nmm is dynamically stable. Temperature-dependent Raman measurements show a deviation of the A1g mode frequency from an anharmonic model below about 165 K, which the authors interpret as a possible signature of a subtle electronic density-wave instability.

Significance. If the structural reassignment is correct, the paper is significant because it challenges the accepted I4/mmm classification of ACu2As2 compounds and adds EuCu2As2 to the small family of locally non-centrosymmetric 122 systems that host density-wave-like instabilities. The work has clear strengths: the DFT phonon calculations are independent first-principles results rather than fits to the Raman peaks, the XRD ambiguity between the two space groups is explicitly acknowledged, the Raman spectra are carefully analyzed, and the authors openly state the limits of their evidence, including the surface-sensitivity of Raman and the absence of CDW signatures. These strengths make the central claim plausible, but the bulk structural conclusion currently rests on a narrow set of computational parameters and the density-wave interpretation is speculative.

major comments (4)
  1. [§2, §3.2, Table 3] The bulk structural claim rests on the DFT prediction that I4/mmm is dynamically unstable, but this is shown for a single computational setup: PBEsol+U with U = 7 eV and an AFM-ordered state. The imaginary Eg mode at -50.07i in Table 3 could depend on the Hubbard U applied to the Eu 4f states or on the magnetic constraint, yet no U-dependence, exchange-correlation functional dependence, or magnetic-order dependence is reported for the phonon instability. Because the authors state, correctly, that Raman cannot distinguish a P4/nmm surface from a P4/nmm bulk, this DFT calculation is the only bulk-sensitive support for the structural reassignment. Without a robustness check of the soft mode, the conclusion that 'the whole structure belongs to the P4/nmm phase' is not fully supported.
  2. [§3.2, Fig. 4, Fig. 6] The seven observed peaks are assigned to specific irreducible representations (Eg, B1g, A1g) solely by comparing measured frequencies with the calculated P4/nmm spectrum; no polarization-resolved Raman measurements are reported. As a result, the symmetry labels attached to the modes, which are later used to discuss the displacement pattern of the anomalous A1g mode, are not independently verified. In particular, the assignments of P1 (calculated 106.7 cm−1, observed 115 cm−1) and P2 (calculated 137.4 cm−1, observed 126 cm−1) show discrepancies of 8–11 cm−1, and possible contributions from two-phonon or defect-related scattering are not discussed. Polarization-resolved measurements on an oriented single crystal would substantially strengthen the mode assignment and the structural conclusion.
  3. [§3.3, Eq. (1), Fig. 7] The phonon anomaly is quantified as the deviation from an anharmonic model fitted to Eq. (1) over a range that is chosen after inspecting the data: the fits are performed between 300 K and 165 K (or 160 K, according to the Fig. 7 caption) and then extrapolated to 80 K. The authors do not report the fitted values of ω0, A, and B, nor any goodness-of-fit measure or residual analysis, so it is difficult to judge whether the extrapolated baseline is reliable. A reproducible assessment would require reporting the fit parameters and uncertainties and testing how the inferred anomaly temperature changes when the fitting window is varied.
  4. [§3.3, §4] The interpretation of the 165 K phonon hardening as a 'subtle electronic density wave instability' is presented without the characteristic signatures that would distinguish a density wave from other electronic or magnetic couplings; the authors themselves note that amplitude modes, zone-folded modes, and two-phonon modes were not observed. The susceptibility deviation in Fig. 3(b) is small, and its fit range is also defined relative to 165 K. The phonon anomaly itself is well documented, but the density-wave conclusion remains one of several possibilities. The abstract and summary should be tempered unless additional evidence, such as superlattice reflections, transport anomalies, or heat-capacity features, is provided.
minor comments (5)
  1. [Throughout] There is an inconsistency in the author list header ('V aitheeswaran' should be 'Vaitheeswaran') and the text contains typos such as 'N'eel', 'focussing', and 'contrary to that what is expected'. The manuscript would benefit from a careful proofreading pass.
  2. [§2] The description of the supercell used for the force-constant calculation, '2√2×2√2×1 conventional cells', is difficult to parse; the authors should clarify the exact supercell geometry and the number of atoms used.
  3. [§3.3, Eq. (1)] Equation (1) uses 'K_B' and later 'KBT' in the exponentials; the Boltzmann constant should be denoted consistently (typically k_B), and the temperature dependence should be written unambiguously.
  4. [§3.1, Fig. 3(b)] The contour plot overlaid in Fig. 3(b) is not clearly described in the caption; the reader cannot tell which color scale corresponds to the Raman shift evolution. A separate panel or a clearer caption would help.
  5. [§3.2, Table 2] The notation 'Theo. (NM)' and 'Theo. (AFM)' is defined in the table, but the differences between non-magnetic and antiferromagnetic results are not discussed in the text; a brief comment on why the AFM frequencies were used for comparison would be useful.

Circularity Check

0 steps flagged · score 1.0 of 10

No significant circularity: the Raman frequencies are compared with independent DFT phonon predictions, and the 165 K anomaly is measured against an anharmonic fit extrapolated outside its fitted range.

full rationale

The central derivations are self-contained. The structural reassignment rests on counting more Raman peaks than the four Raman-active modes allowed by I4/mmm, and on DFT phonon calculations for both I4/mmm and P4/nmm that were performed with fixed PBEsol+U parameters and no adjustment to the measured peak positions. The calculated P4/nmm frequencies are presented alongside the observed P1-P7 peaks as a comparison, not as fit outputs; the I4/mmm soft mode at -50.07i is an independent first-principles result. The temperature analysis likewise fits the standard anharmonic expression Eq. (1) only to the 300-165 K window and extrapolates to 80 K; the low-temperature hardening is therefore an observed deviation from an independent baseline, not a parameter renamed as a prediction. The paper explicitly acknowledges that Raman is a surface probe and that surface P4/nmm with bulk I4/mmm cannot be excluded purely experimentally; it relies on bulk DFT to settle this, which is an honest limitation rather than a circular step. The only co-author citations (e.g., Refs. [18], [19], [44]) are background context or illustrative displacement patterns and are not load-bearing for the main claim. Correctness concerns about the untested U=7 eV choice and the absence of bulk-sensitive confirmation are real but belong to risk assessment, not circularity.

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

The structural claim relies on DFT+U phonon calculations with a hand-set U value, on the assumption that the observed Raman bands are intrinsic first-order modes, and on an anharmonic baseline model whose extrapolation defines the anomaly. The density wave interpretation adds a postulated electronic phase with no direct evidence. These are the main items the reader must accept upstream.

free parameters (4)
  • U (DFT+U on Eu f electrons) = 7 eV
    Dudarev +U parameter chosen by hand; affects phonon frequencies and the I4/mmm instability that supports the structural claim. No U-dependence study is reported.
  • Anharmonic baseline parameters (omega_0, A, B) per tracked mode = not reported in text
    Fit to 165-300 K data using Eq. (1); the extrapolated baseline defines the magnitude of the claimed anomaly, so the anomaly claim depends on these fitted values.
  • Lorentzian peak parameters (position, width, intensity) = peak positions at 80 K: 115,126,150,170,201,224,235 cm^-1
    Peak positions are obtained by fitting; the seven-mode count and frequencies are the core evidence for P4/nmm.
  • Curie-Weiss parameters C, theta = mu_eff = 7.74 mu_B (theta not stated)
    Used to subtract the Eu^2+ magnetic contribution and infer a susceptibility deviation below 165 K; fit restricted to T > 180 K and extrapolated.
assumptions (4)
  • domain assumption GGA-PBEsol + DFT+U (U=7 eV) provides phonon frequencies and dynamical stability accurate enough to discriminate I4/mmm from P4/nmm.
    Used in Sec. 2 and Sec. 3.2; the conclusion that I4/mmm is unstable rests on this approximation.
  • domain assumption The seven bands observed between 115 and 235 cm^-1 are intrinsic first-order Raman modes of EuCu2As2.
    Assumed in Sec. 3.2; no polarization analysis or impurity/surface-mode check is presented.
  • domain assumption The anharmonic decay model of Balkanski et al. (Eq. 1) with no explicit thermal-expansion or spin/electronic coupling terms describes the baseline phonon shift down to 80 K.
    Used in Sec. 3.3 to define the anomaly; deviations from this model are interpreted as a phase transition.
  • domain assumption The Curie-Weiss law holds above 180 K and extrapolates to 100 K for the Eu^2+ magnetic contribution.
    Used in Sec. 3.1 to generate the susceptibility residual interpreted as a second anomaly near 165 K.
invented entities (1)
  • Subtle electronic density wave instability below 165 K
    purpose: Explains the hardening and linewidth narrowing of the A1g mode and similar smaller anomalies in other modes.
    No superlattice reflections, amplitude modes, zone-folded modes, or transport signatures are presented; the authors explicitly state these CDW signatures were not identified. The entity is inferred from the phonon anomaly alone.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Evidences for local non-centrosymmetricity and strong phonon anomaly in EuCu2As2: A Raman spectroscopy and lattice dynamics study." pith.science (2026). https://pith.science/paper/YDJQ7MIB

@misc{pith2026250105296,
  author       = {Pith},
  title        = {Pith review of: Evidences for local non-centrosymmetricity and strong phonon anomaly in EuCu2As2: A Raman spectroscopy and lattice dynamics study},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/YDJQ7MIB}},
  note         = {Machine review of arXiv:2501.05296}
}
abstract

Phonon modes and their association with the electronic states have been investigated for the metallic EuCu$_{2}$As$_{2}$ system. In this work, we present the Raman spectra of this pnictide system which clearly shows the presence of seven well defined peaks above $100$~cm$^{-1}$ that is consistent with the locally non-centrosymmetric {\it P4/nmm} crystal structure, contrary to that what is expected from the accepted symmorphic {\it I4/mmm} structure. Lattice dynamics calculations using the {\it P4/nmm} symmetry attest that there is a commendable agreement between the calculated phonon spectra at the $\Gamma$ point and the observed Raman mode frequencies, with the most intense peak at $\sim 232$~cm$^{-1}$ being ascribed to the A$_{1g}$ mode. Temperature dependent Raman measurements show that there is a significant deviation from the expected anharmonic behaviour around $165$~K for the A$_{1g}$ mode, with anomalies being observed for several other modes as well, although to a lesser extent. Attempts are made to rationalize the observed anomalous behavior related to the hardening of the phonon modes, with parallels being drawn from metal dichalcogenide and allied systems. Similarities in the evolution of the Raman peak frequencies with temperature seem to suggest a strong signature of a subtle electronic density wave instability below $165$~K in this compound.

Figures

Figures reproduced from arXiv: 2501.05296 by the authors.

Figure 1
Figure 1. Crystal structure of EuCu2As2 in two polymorphous phases: (a) ThCr2Si2- like structure (I4/mmm symmetry), and (b) CaBe2Ge2-like structure (P4/nmm symmetry) [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗
Figure 2
Figure 2. Powder X-ray diffraction pattern (with Cu - K [PITH_FULL_IMAGE:figures/full_fig_p005_2.png] view at source ↗
Figure 3
Figure 3. (a) Magnetic susceptibility plot of EuCu [PITH_FULL_IMAGE:figures/full_fig_p007_3.png] view at source ↗
Figures from the paper (4 more)
Figure 4
Figure 4. Figure 4: Background subtracted Raman spectra of EuCu [PITH_FULL_IMAGE:figures/full_fig_p008_4.png]
Figure 5
Figure 5. Figure 5: Phonon dispersion curves (a,c) and phonon density of states (b,d) for [PITH_FULL_IMAGE:figures/full_fig_p009_5.png]
Figure 6
Figure 6. Figure 6: Atoms displacement realized by the Raman active modes for EuCu [PITH_FULL_IMAGE:figures/full_fig_p011_6.png]
Figure 7
Figure 7. Figure 7: (a) Characteristic temperature dependent Raman spectra of EuCu [PITH_FULL_IMAGE:figures/full_fig_p012_7.png]

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

53 extracted references · 36 canonical work pages

  1. [1]

    Steglich F, Aarts J, Bredl C D, Lieke W, Meschede D, Franz W and Sch¨ afer H 1979 Phys. Rev. Lett. 43 1892 URL https://doi.org/10.1103/PhysRevLett.43.1892

    work page doi:10.1103/physrevlett.43.1892 1979

  2. [2]

    Stockert O, Arndt J, Faulhaber E, Geibel C, Jeevan H S, Kirchner S, Loewenhaupt M, Schmalzl K, Schmidt W, Si Q and Steglich F 2011 Nat. Phys. 7 119 URL https://doi.org/10.1038/ nphys1852

    work page 2011

  3. [3]

    Ni N, Nandi S, Kreyssig A, Goldman A, Mun E, Bud’ko S and Canfield P 2008 Physical Review B 78 014523

    work page 2008

  4. [4]

    Phys.: Condens

    Li L, Parker D S, Gai Z, Cao H B and Sefat A S 2020 J. Phys.: Condens. Matter 32 295602 URL https://doi.org/10.1088/1361-648X/ab7e60

    work page doi:10.1088/1361-648x/ab7e60 2020

  5. [5]

    Kudo K, Nishikubo Y and Nohara M 2010 J. Phys. Soc. Jpn. 79 123710 URL https: //doi.org/10.1143/JPSJ.79.123710

    doi:10.1143/jpsj.79.123710 2010

  6. [6]

    Nagano Y, Araoka N, Mitsuda A, Yayama H, Wada H, Ichihara M, Isobe M and Ueda Y 2013 J. Phys. Soc. Jpn. 82 064715 URL https://doi.org/10.7566/JPSJ.82.064715

    doi:10.7566/jpsj.82.064715 2013

  7. [7]

    China Phys

    Mu Q, Pan B, Ruan B, Liu T, Zhao K, Shan L, Chen G and Ren Z 2018 Sci. China Phys. Mech. Astron. 61 127409 URL https://doi.org/10.1007/s11433-018-9285-5

    work page doi:10.1007/s11433-018-9285-5 2018

  8. [8]

    Khim S, Landaeta J F, Banda J, Bannor N, Brando M, Brydon P M R, Hafner D, K¨ uchler R, Cardoso-Gil R, Stockert U, Mackenzie A P, Agterberg D F, Geibel C and Hassinger E 2021 Science 373 1012 URL https://doi.org/10.1126/science.abe7518

    doi:10.1126/science.abe7518 2021

Show all 53 references
  1. [9]

    Rotter M, Tegel M and Johrendt D 2008 Phys. Rev. Lett. 101 107006 URL https://doi.org/ 10.1103/PhysRevLett.101.107006

    2008 doi

  2. [10]

    Sasmal K, Lv B, Lorenz B, Guloy A M, Chen F, Xue Y Y and Chu C W 2008 Phys. Rev. Lett. 101 107007 URL https://doi.org/10.1103/PhysRevLett.101.107007

    2008 doi

  3. [11]

    Torikachvili M S, Bud’ko S L, Ni N and Canfield P C 2008 Phys. Rev. Lett. 101 057006 URL https://doi.org/10.1103/PhysRevLett.101.057006

    2008 doi

  4. [12]

    Zocco D A, Grube K, Eilers F, Wolf T and L¨ ohneysen H v 2013 Phys. Rev. Lett. 111 057007 URL https://doi.org/10.1103/PhysRevLett.111.057007

    2013 doi

  5. [13]

    Cho C W, Yang J H, Yuan N F Q, Shen J, Wolf T and Lortz R 2017 Phys. Rev. Lett. 119 217002 URL https://doi.org/10.1103/PhysRevLett.119.217002

    2017 doi

  6. [14]

    Lin Q, Miller G J and Corbett J D 2014 Inorg. Chem. 53 5875 URL https://doi.org/10.1021/ ic402991d

    2014

  7. [15]

    Wang H C, Botti S and Marques M A L 2021 npj Comput. Mater. 7 12 URL https: //doi.org/10.1038/s41524-020-00481-6

    2021 doi

  8. [16]

    Singh D J 2009 Phys. Rev. B 79 153102 URL https://doi.org/10.1103/PhysRevB.79.153102

    2009 doi

  9. [17]

    Wu S F, Richard P, van Roekeghem A, Nie S M, Miao H, Xu N, Qian T, Saparov B, Fang Z, Biermann S, Sefat A S and Ding H 2015 Phys. Rev. B 91 235109 URL https: //doi.org/10.1103/PhysRevB.91.235109

    2015 doi

  10. [18]

    Das S D, Laad M S, Craco L, Gillett J, Tripathi V and Sebastian S E 2015 Phys. Rev. B 92 155112 URL https://doi.org/10.1103/PhysRevB.92.155112 16

    2015 doi

  11. [19]

    Ptok A, Kapcia K J, Jochym P T, /suppress La˙ zewski J, Ole´ s A M and Piekarz P 2021Phys. Rev. B 104 L041109 URL https://doi.org/10.1103/PhysRevB.104.L041109

    doi

  12. [20]

    Hafner D, Khanenko P, Eljaouhari E O, K¨ uchler R, Banda J, Bannor N, L¨ uhmann T, Landaeta J F, Mishra S, Sheikin I, Hassinger E, Khim S, Geibel C, Zwicknagl G and Brando M 2022 Phys. Rev. X 12 011023 URL https://doi.org/10.1103/PhysRevX.12.011023

    2022 doi

  13. [21]

    Sengupta K, Paulose P L, Sampathkumaran E V, Doert T and Jemetio J P F 2005 Phys. Rev. B 72 184424 URL https://doi.org/10.1103/PhysRevB.72.184424

    2005 doi

  14. [22]

    Phys.: Condens

    Sengupta K, Alzamora M, Fontes M B, Sampathkumaran E V, Ramos S M, Hering E N, Saitovitch E M B, Paulose P L, Ranganathan R, Doert T and Jemetio J P F 2012 J. Phys.: Condens. Matter 24 096004 URL https://doi.org/10.1088/0953-8984/24/9/096004

    2012 doi

  15. [23]

    Anand V K and Johnston D C 2015 Phys. Rev. B 91 184403 URL https://doi.org/10.1103/ PhysRevB.91.184403

    2015

  16. [25]

    Phys.: Condens

    Adhikary G, Sahadev N, Biswas D, Bindu R, Kumar N, Thamizhavel A, Dhar S K and Maiti K 2013 J. Phys.: Condens. Matter 25 225701 URL https://doi.org/10.1088/0953-8984/25/ 22/225701

    2013 doi

  17. [26]

    Bl¨ ochl P E 1994Phys. Rev. B 50 17953 URL https://doi.org/10.1103/PhysRevB.50.17953

    doi

  18. [28]

    Perdew J P, Ruzsinszky A, Csonka G I, Vydrov O A, Scuseria G E, Constantin L A, Zhou X and Burke K 2008 Phys. Rev. Lett. 100 136406 URL https://doi.org/10.1103/PhysRevLett. 100.136406

    2008 doi

  19. [29]

    Dudarev S L, Botton G A, Savrasov S Y, Humphreys C J and Sutton A P 1998 Phys. Rev. B 57 1505 URL https://doi.org/10.1103/PhysRevB.57.1505

    1998 doi

  20. [30]

    Monkhorst H J and Pack J D 1976 Phys. Rev. B 13 5188 URL https://doi.org/10.1103/ PhysRevB.13.5188

    1976

  21. [31]

    Stokes H T and Hatch D M 2005 J. Appl. Cryst. 38 237 URL https://doi.org/10.1107/ S0021889804031528

    2005

  22. [32]

    Togo A and Tanaka I 2018 Spglib: a software library for crystal symmetry search ( Preprint arXiv:1808.01590)

    2018 arXiv

  23. [33]

    Hinuma Y, Pizzi G, Kumagai Y, Oba F and Tanaka I 2017 Comput. Mater. Sci. 128 140 URL https://doi.org/10.1016/j.commatsci.2016.10.015

    2017 doi

  24. [34]

    Parlinski K, Li Z Q and Kawazoe Y 1997 Phys. Rev. Lett. 78 4063 URL https://doi.org/10. 1103/PhysRevLett.78.4063

    1997

  25. [35]

    Phys.: Condens

    Tadano T, Gohda Y and Tsuneyuki S 2014 J. Phys.: Condens. Matter 26 225402 URL https://doi.org/10.1088/0953-8984/26/22/225402

    2014 doi

  26. [36]

    Togo A, Chaput L, Tadano T and Tanaka I 2023 J. Phys. Condens. Matter 35 353001

    2023

  27. [37]

    D¨ unner J, Mewis A, Roepke M and Michels G 1995 Z. anorg. allg. Chem. 621 1523 URL https://doi.org/10.1002/zaac.19956210915

    1995 doi

  28. [38]

    Das S, McFadden K, Singh Y, Nath R, Ellern A and Johnston D C 2010 Phys. Rev. B 81 054425 URL https://ldoi.org/10.1103/PhysRevB.81.054425

    2010 doi

  29. [39]

    Rotter M, Tegel M, Johrendt D, Schellenberg I, Hermes W and P¨ ottgen R 2008 Phys. Rev. B 78 020503(R) URL https://doi.org/10.1103/PhysRevB.78.020503

    2008 doi

  30. [40]

    Krellner C, Caroca-Canales N, Jesche A, Rosner H, Ormeci A and Geibel C 2008 Phys. Rev. B 78 100504(R) URL https://doi.org/10.1103/PhysRevB.78.100504

    2008 doi

  31. [41]

    Litvinchuk A P, Hadjiev V G, Iliev M N, Lv B, Guloy A M and Chu C W 2008 Phys. Rev. B 78 060503(R) URL https://doi.org/10.1103/PhysRevB.78.060503

    2008 doi

  32. [42]

    Phys.: Condens

    Wdowik U D, Jag/suppress lo G and Piekarz P 2015J. Phys.: Condens. Matter 27 415403 URL https://doi.org/10.1088/0953-8984/27/41/415403

    doi

  33. [43]

    Baum A, Li Y, Tomi´ c M, Lazarevi´ c N, Jost D, L¨ offler F, Muschler B, B¨ ohm T, Chu J H, Fisher I R, Valent ´ ı R, Mazin I I and Hackl R 2018 Phys. Rev. B 98 075113 URL https: //doi.org/10.1103/PhysRevB.98.075113

    2018 doi

  34. [44]

    Ptok A, Sternik M, Kapcia K J and Piekarz P 2019 Phys. Rev. B 99 134103 URL https: //doi.org/10.1103/PhysRevB.99.134103

    2019 doi

  35. [45]

    Balkanski M, Wallis R F and Haro E 1983 Phys. Rev. B 28 1928 URL https://doi.org/10. 1103/PhysRevB.28.1928

    1983

  36. [46]

    13 443 URL https://doi.org/10.1038/s41467-021-27267-8 17

    Weber M C, Guennou M, Evans D M, Toulouse C, Simonov A, Kholina Y, Ma X, Ren W, Cao S, Carpenter M A, Dkhil B, Fiebig M and Kreisel J 2022 Nature Commun. 13 443 URL https://doi.org/10.1038/s41467-021-27267-8 17

    2022 doi

  37. [47]

    Hill H M, Chowdhury S, Simpson J R, Rigosi A F, Newell D B, Berger H, Tavazza F and Hight Walker A R 2019 Phys. Rev. B 99 174110 URL https://doi.org/10.1103/PhysRevB. 99.174110

    2019 doi

  38. [48]

    Sharafeev A, Gnezdilov V, Sankar R, Chou F C and Lemmens P 2017 Phys. Rev. B 95 235148 URL https://doi.org/10.1103/PhysRevB.95.235148

    2017 doi

  39. [49]

    Lin D, Li S, Wen J, Berger H, Forr´ o L, Zhou H, Jia S, Taniguchi T, Watanabe K, Xi X and Bahramy M S 2020 Nat. Commun. 11 2406 URL https://doi.org/10.1038/ s41467-020-15715-w

    2020

  40. [50]

    Joshi J, Hill H M, Chowdhury S, Malliakas C D, Tavazza F, Chatterjee U, Hight Walker A R and Vora P M 2019Phys. Rev. B 99 245144 URL https://doi.org/10.1103/PhysRevB.99.245144

    doi

  41. [51]

    13 3461 URL https: //doi.org/10.1038/s41467-022-31162-1

    Liu G, Ma X, He K, Li Q, Tan H, Liu Y, Xu J, Tang W, Watanabe K, Taniguchi T, Gao L, Dai Y, Wen H H, Yan B and Xi X 2022 Nature Commun. 13 3461 URL https: //doi.org/10.1038/s41467-022-31162-1

    2022 doi

  42. [52]

    Kawasaki S, Tani Y, Mabuchi T, Kudo K, Nishikubo Y, Mitsuoka D, Nohara M and Zheng G q 2015 Phys. Rev. B 91 060510(R) URL https://doi.org/10.1103/PhysRevB.91.060510

    2015 doi

  43. [53]

    Xiao Y, Su Y, Meven M, Mittal R, Kumar C M N, Chatterji T, Price S, Persson J, Kumar N, Dhar S K, Thamizhavel A and Brueckel T 2009 Phys. Rev. B 80 174424 URL https: //doi.org/10.1103/PhysRevB.80.174424

    2009 doi

  44. [54]

    Overhauser A W 1968 Phys. Rev. 167 691 URL https://doi.org/10.1103/PhysRev.167.691

    1968 doi

  45. [55]

    Momma K and Izumi F 2011 J. Appl. Crystallogr. 44 1272 URL http://doi.org/10.1107/ S0021889811038970 1 Supplemental Material Evidences for local non-centrosymmetricity and strong phonon anomaly in EuCu 2As2: A Raman spectroscopy and lattice dynamics study D. Swain et al. (Date...

    2011 arXiv

Pith tools

Reviewed August 10, 2026 · model on record in the stance chip above.