Reversible Superdense Ordering of Tetragonal Lithium in a Layered Material
Pith reviewed 2026-06-28 09:19 UTC · model grok-4.3
The pith
At Li3LaTe3 a reversible three-layer tetragonal lithium phase occupies the van der Waals gap of LaTe3.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
Integration of imaging, spectroscopy, and diffraction within a single in-situ STEM experiment on LaTe3 shows that Li3LaTe3 contains a new three-layer superdense lithium phase with tetragonal symmetry inside the van der Waals gap; this phase is fully reversible upon electrochemical cycling.
What carries the argument
Multimodal STEM that simultaneously records atomic-resolution images, elemental maps, and diffraction patterns inside an operating electrochemical cell to locate and identify lithium atoms.
If this is right
- Lithium ordering in layered hosts can reach x=3 with a tetragonal rather than hexagonal arrangement.
- The superdense phase sits in the van der Waals gap and can be inserted and extracted repeatedly without loss of reversibility.
- In-plane lattice expansion reaches 5 percent as the ordered phases form.
- Complete lithium ordering sequences can now be followed in real time with one experimental platform.
Where Pith is reading between the lines
- The same multimodal approach could be applied to other van der Waals tellurides or selenides to search for analogous superdense phases.
- The tetragonal symmetry may change lithium jump barriers relative to the more common hexagonal stacking.
- Device-level cycling tests would reveal whether the high lithium density improves usable capacity in a full cell.
Load-bearing premise
The combined imaging, spectroscopy, and diffraction signals unambiguously locate the lithium atoms and confirm the tetragonal symmetry without being produced by beam damage or overlapping signals.
What would settle it
A neutron or synchrotron diffraction measurement on bulk Li3LaTe3 that shows no tetragonal reflections attributable to a three-layer interlayer lithium arrangement would disprove the phase.
Figures
read the original abstract
Understanding lithium (Li) ordering and dynamics is foundational in energy storage. X-ray based experimental methods do not simultaneously provide atomic structure information together with chemical composition and local bonding information for lithium in solids. Here we employ scanning transmission electron microscopy (STEM) and combine imaging, spectroscopy, and diffraction within a single experiment, to observe, in situ, an all-solid-state electrochemical cell. By integrating multimodal STEM with other complementary techniques, we report a complete mapping of lithium intercalation in a layered system, LaTe3. We identify three ordered phases of LixLaTe3 with x ranging from 1/3 to 3 with in-plane strain of up to 5%. At a very high lithium concentration of Li3LaTe3, we discover an unexpected three-layer, superdense lithium phase with tetragonal symmetry occupying the van der Waals gap. This represents a new Li phase that is reversible. Our multimodal approach thus enables complete tracking of lithium ordering and dynamics, important for next-generation energy storage applications.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The manuscript reports an in-situ multimodal STEM study (HAADF/ABF imaging, EELS/EDX spectroscopy, and diffraction) of lithium intercalation in an all-solid-state electrochemical cell based on layered LaTe3. It identifies three ordered LixLaTe3 phases (x ranging from 1/3 to 3) with up to 5% in-plane strain and claims the discovery, at x=3, of a reversible three-layer superdense lithium phase with tetragonal symmetry occupying the van der Waals gap.
Significance. If the phase identification holds after artifact controls, the result would be significant for energy-storage research by demonstrating a new, high-concentration Li ordering motif and by showing that combined STEM modalities can track Li positions and dynamics at the atomic scale in an operating cell. The integration of multiple signals within a single in-situ experiment is a methodological strength.
major comments (2)
- [Abstract / multimodal experiment description] Abstract and multimodal-experiment paragraph: the claim that the combined HAADF/ABF, EELS/EDX, and diffraction signals unambiguously locate Li atoms in a three-layer tetragonal arrangement at x=3 rests on unshown quantitative controls; no dose-series data, simulated diffraction patterns for artifact models, or explicit discussion of beam-damage products versus the reported ordering is supplied, which is load-bearing for the central identification of a new reversible Li phase.
- [Abstract] Abstract: the reported in-plane strain of up to 5% and the three ordered phases lack accompanying error bars, measurement method, or tabulated values, preventing assessment of whether the strain distinguishes the tetragonal phase from possible projection overlaps or electrolyte residues.
minor comments (1)
- [Abstract] The abstract states that X-ray methods cannot simultaneously provide atomic structure, composition, and bonding information, but does not cite specific prior X-ray work on LaTe3 or related layered tellurides for context.
Simulated Author's Rebuttal
We thank the referee for their careful reading and constructive comments on our manuscript. The points raised highlight important aspects of experimental rigor that we will address in revision. We respond to each major comment below.
read point-by-point responses
-
Referee: [Abstract / multimodal experiment description] Abstract and multimodal-experiment paragraph: the claim that the combined HAADF/ABF, EELS/EDX, and diffraction signals unambiguously locate Li atoms in a three-layer tetragonal arrangement at x=3 rests on unshown quantitative controls; no dose-series data, simulated diffraction patterns for artifact models, or explicit discussion of beam-damage products versus the reported ordering is supplied, which is load-bearing for the central identification of a new reversible Li phase.
Authors: We agree that the manuscript as submitted does not include the requested quantitative controls. In the revised version we will add (i) dose-series data acquired on the same regions to demonstrate stability of the observed ordering under the imaging conditions used, (ii) multislice simulated diffraction patterns for the proposed three-layer tetragonal Li model together with alternative artifact models (projection overlaps, electrolyte residues, and beam-induced disorder), and (iii) an explicit discussion section comparing possible beam-damage signatures to the reversible, concentration-dependent ordering we report. These additions will be referenced from the abstract and methods. revision: yes
-
Referee: [Abstract] Abstract: the reported in-plane strain of up to 5% and the three ordered phases lack accompanying error bars, measurement method, or tabulated values, preventing assessment of whether the strain distinguishes the tetragonal phase from possible projection overlaps or electrolyte residues.
Authors: We accept this criticism. The revised manuscript will include (i) a clear description of the strain measurement protocol (lattice-parameter extraction from calibrated diffraction patterns cross-validated with atomic-column positions in HAADF images), (ii) tabulated strain values for each of the three phases together with standard deviations derived from multiple regions and independent measurements, and (iii) explicit comparison showing that the measured strains exceed those expected from projection or residue artifacts. Error bars will also be added to the abstract where space permits or noted as supplementary information. revision: yes
Circularity Check
No circularity: purely observational experimental report with no derivation chain or fitted predictions
full rationale
The paper is an experimental report on in-situ STEM multimodal imaging, spectroscopy, and diffraction of lithium intercalation in LaTe3. It identifies ordered phases and a new tetragonal Li phase at x=3 based on observed contrast changes, spectral maps, and diffraction patterns. No equations, first-principles derivations, parameter fits, or predictions are present that could reduce to inputs by construction. No self-citation chains or ansatzes are invoked to support any claimed result. The central claim rests on direct experimental signals rather than any self-referential logic, consistent with the reader's assessment of score 0.0. The skeptic's concerns address potential experimental artifacts and signal interpretation but do not indicate circularity in any derivation.
Axiom & Free-Parameter Ledger
Reference graph
Works this paper leans on
-
[1]
N. A. Cañas, P. Einsiedel, O. T. Freitag, C. Heim, M. Steinhauer, D.-W. Park, K. A. Friedrich, Operando X-ray diffraction during battery cycling at elevated temperatures: A quantitative analysis of lithium-graphite intercalation compounds. Carbon 116, 255–263 (2017)
2017
-
[2]
X. Yu, Y. Lyu, L. Gu, H. Wu, S.-M. Bak, Y. Zhou, K. Amine, S. N. Ehrlich, H. Li, K.-W. Nam, X.-Q. Yang, Understanding the Rate Capability of High-Energy-Density Li-Rich Layered Li1.2Ni0.15Co0.1Mn0.55O2 Cathode Materials. Advanced Energy Materials 4, 1300950 (2014)
2014
-
[3]
Mukai, T
K. Mukai, T. Uyama, T. Inoue, H. Saitoh, In situ X-ray diffraction studies on nominal composition of C2Li under high pressure and temperature. Sci Rep 14, 26307 (2024)
2024
-
[4]
Zhou, J.-L
Y.-N. Zhou, J.-L. Yue, E. Hu, H. Li, L. Gu, K.-W. Nam, S.-M. Bak, X. Yu, J. Liu, J. Bai, E. Dooryhee, Z.-W. Fu, X.-Q. Yang, High-Rate Charging Induced Intermediate Phases and Structural Changes of Layer-Structured Cathode for Lithium-Ion Batteries. Advanced Energy Materials 6, 1600597 (2016)
2016
-
[5]
X. Liu, D. Wang, G. Liu, V. Srinivasan, Z. Liu, Z. Hussain, W. Yang, Distinct charge dynamics in battery electrodes revealed by in situ and operando soft X-ray spectroscopy. Nat Commun 4, 2568 (2013)
2013
-
[6]
H. Liu, H. Liu, S. H. Lapidus, Y. S. Meng, P. J. Chupas, K. W. Chapman, Sensitivity and Limitations of Structures from X-ray and Neutron-Based Diffraction Analyses of Transition Metal Oxide Lithium-Battery Electrodes. J. Electrochem. Soc. 164, A1802 (2017)
2017
-
[7]
Missyul, I
A. Missyul, I. Bolshakov, R. Shpanchenko, XRD study of phase transformations in lithiated graphite anodes by Rietveld method. Powder Diffraction 32, S56–S62 (2017)
2017
-
[8]
Senyshyn, O
A. Senyshyn, O. Dolotko, M. J. Mühlbauer, K. Nikolowski, H. Fuess, H. Ehrenberg, Lithium Intercalation into Graphitic Carbons Revisited: Experimental Evidence for Twisted Bilayer Behavior. J. Electrochem. Soc. 160, A3198 (2013)
2013
-
[9]
D. P. Finegan, A. Quinn, D. S. Wragg, A. M. Colclasure, X. Lu, C. Tan, T. M. M. Heenan, R. Jervis, D. J. L. Brett, S. Das, T. Gao, D. A. Cogswell, M. Z. Bazant, M. D. Michiel, S. Checchia, P. R. Shearing, K. Smith, Spatial dynamics of lithiation and lithium plating during high-rate operation of graphite electrodes. Energy Environ. Sci. 13, 2570–2584 (2020)
2020
-
[10]
H. T. Philipp, M. W. Tate, K. S. Shanks, L. Mele, M. Peemen, P. Dona, R. Hartong, G. van Veen, Y.-T. Shao, Z. Chen, J. Thom-Levy, D. A. Muller, S. M. Gruner, Very-High Dynamic Range, 10,000 Frames/Second Pixel Array Detector for Electron Microscopy. Microanal 28, 425–440 (2022)
2022
-
[11]
A Synchrotron in a Microscope
L. M. Brown, “A Synchrotron in a Microscope” in Electron Microscopy and Analysis 1997, Proceedings of the Institute of Physics Electron Microscopy and Analysis Group Conference, University of Cambridge, 2-5 September 1997 (CRC Press, 1997)
1997
-
[12]
X. Wang, M. Zhang, J. Alvarado, S. Wang, M. Sina, B. Lu, J. Bouwer, W. Xu, J. Xiao, J.- G. Zhang, J. Liu, Y. S. Meng, New Insights on the Structure of Electrochemically Deposited Lithium Metal and Its Solid Electrolyte Interphases via Cryogenic TEM. Nano Lett. 17, 7606–7612 (2017)
2017
-
[13]
M. J. Zachman, Z. Tu, S. Choudhury, L. A. Archer, L. F. Kourkoutis, Cryo-STEM mapping of solid–liquid interfaces and dendrites in lithium-metal batteries. Nature 560, 345–349 (2018)
2018
-
[14]
Y. Li, Y. Li, A. Pei, K. Yan, Y. Sun, C.-L. Wu, L.-M. Joubert, R. Chin, A. L. Koh, Y. Yu, J. Perrino, B. Butz, S. Chu, Y. Cui, Atomic structure of sensitive battery materials and interfaces revealed by cryo–electron microscopy. Science 358, 506–510 (2017)
2017
-
[15]
Serra-Maia, P
R. Serra-Maia, P. Kumar, A. C. Meng, A. C. Foucher, Y. Kang, K. Karki, D. Jariwala, E. A. Stach, Nanoscale Chemical and Structural Analysis during In Situ Scanning/Transmission Electron Microscopy in Liquids. ACS Nano 15, 10228–10240 (2021)
2021
-
[16]
Zhang, Z
Q. Zhang, Z. Song, X. Sun, Y. Liu, J. Wan, S. B. Betzler, Q. Zheng, J. Shangguan, K. C. Bustillo, P. Ercius, P. Narang, Y. Huang, H. Zheng, Atomic dynamics of electrified solid– liquid interfaces in liquid-cell TEM. Nature 630, 643–647 (2024)
2024
-
[17]
S. Kim, V. Briega-Martos, S. Liu, K. Je, C. Shi, K. M. Stephens, S. E. Zeltmann, Z. Zhang, R. Guzman-Soriano, W. Li, J. Jiang, J. Choi, Y. J. Negash, F. S. I. Walden, N. L. Jr. Marthe, P. S. Wellborn, Y. Guo, J. Damiano, Y. Han, E. H. Thiede, Y. Yang, Operando Heating and Cooling Electrochemical 4D-STEM Probing Nanoscale Dynamics at Solid– Liquid Interfac...
2025
-
[18]
Z. Wang, D. Santhanagopalan, W. Zhang, F. Wang, H. L. Xin, K. He, J. Li, N. Dudney, Y. S. Meng, In Situ STEM-EELS Observation of Nanoscale Interfacial Phenomena in All- Solid-State Batteries. Nano Lett. 16, 3760–3767 (2016)
2016
-
[19]
M. T. McDowell, Z. Lu, K. J. Koski, J. H. Yu, G. Zheng, Y. Cui, In Situ Observation of Divergent Phase Transformations in Individual Sulfide Nanocrystals. Nano Lett. 15, 1264– 1271 (2015)
2015
-
[20]
M. T. McDowell, S. W. Lee, J. T. Harris, B. A. Korgel, C. Wang, W. D. Nix, Y. Cui, In Situ TEM of Two-Phase Lithiation of Amorphous Silicon Nanospheres. Nano Lett. 13, 758–764 (2013)
2013
-
[21]
Kühne, F
M. Kühne, F. Börrnert, S. Fecher, M. Ghorbani-Asl, J. Biskupek, D. Samuelis, A. V. Krasheninnikov, U. Kaiser, J. H. Smet, Reversible superdense ordering of lithium between two graphene sheets. Nature 564, 234–239 (2018)
2018
-
[22]
Y. Wang, I. Petrides, G. McNamara, M. M. Hosen, S. Lei, Y.-C. Wu, J. L. Hart, H. Lv, J. Yan, D. Xiao, J. J. Cha, P. Narang, L. M. Schoop, K. S. Burch, Axial Higgs mode detected by quantum pathway interference in RTe3. Nature 606, 896–901 (2022)
2022
-
[23]
Singh, G
B. Singh, G. McNamara, K.-M. Kim, S. Siddique, S. D. Funni, W. Zhang, X. Luo, P. Sakrikar, E. M. Kenney, R. Singha, S. Alekseev, S. A. A. Ghorashi, T. J. Hicken, C. Baines, H. Luetkens, Y. Wang, V. M. Plisson, M. Geiwitz, C. A. Occhialini, R. Comin, M. J. Graf, L. Zhao, J. Cano, R. M. Fernandes, J. J. Cha, L. M. Schoop, K. S. Burch, Ferroaxial density wav...
2025
-
[24]
Ophus, Four-Dimensional Scanning Transmission Electron Microscopy (4D-STEM): From Scanning Nanodiffraction to Ptychography and Beyond
C. Ophus, Four-Dimensional Scanning Transmission Electron Microscopy (4D-STEM): From Scanning Nanodiffraction to Ptychography and Beyond. Microscopy and Microanalysis 25, 563–582 (2019)
2019
-
[25]
Sarkar, J
S. Sarkar, J. Bhattacharya, P. Sadhukhan, D. Curcio, R. Dutt, V. K. Singh, M. Bianchi, A. Pariari, S. Roy, P. Mandal, T. Das, P. Hofmann, A. Chakrabarti, S. Roy Barman, Charge density wave induced nodal lines in LaTe3. Nat Commun 14, 3628 (2023)
2023
-
[26]
M. R. Nadler, C. P. Kempier, Crystallographic Data 186. Lithium. Anal. Chem. 31, 2109– 2109 (1959)
1959
-
[27]
Hightower, C
A. Hightower, C. C. Ahn, B. Fultz, P. Rez, Electron energy-loss spectrometry on lithiated graphite. Appl. Phys. Lett. 77, 238–240 (2000)
2000
-
[28]
Brouet, W
V. Brouet, W. L. Yang, X. J. Zhou, Z. Hussain, R. G. Moore, R. He, D. H. Lu, Z. X. Shen, J. Laverock, S. B. Dugdale, N. Ru, I. R. Fisher, Angle-resolved photoemission study of the evolution of band structure and charge density wave properties in R Te 3 ( R = Y , La, Ce, Sm, Gd, Tb, and Dy). Phys. Rev. B 77, 235104 (2008)
2008
-
[29]
M. Wang, A. Kumar, H. Dong, J. M. Woods, J. V. Pondick, S. Xu, D. J. Hynek, P. Guo, D. Y. Qiu, J. J. Cha, A Gapped Phase in Semimetallic Td-WTe2 Induced by Lithium Intercalation. Advanced Materials 34, 2200861 (2022)
2022
-
[30]
S. Xu, K. Evans-Lutterodt, S. Li, N. L. Williams, B. Hou, J. J. Huang, M. G. Boebinger, S. Lee, M. Wang, A. Singer, P. Guo, D. Y. Qiu, J. J. Cha, Lithiation Induced Phases in 1T′- MoTe2 Nanoflakes. ACS Nano 18, 17349–17358 (2024)
2024
-
[31]
Kopaczek, K
J. Kopaczek, K. Yumigeta, A. Ibrahim, M. Y. Sayyad, S. Sinha, R. Sailus, P. Hays, S. T. R. Moosavy, S. Susarla, C. Ataca, R. Kudrawiec, S. Tongay, Experimental and Theoretical Studies of the Surface Oxidation Process of Rare-Earth Tritellurides. Advanced Electronic Materials 9, 2201129 (2023)
2023
-
[32]
Kopaczek, H
J. Kopaczek, H. Li, K. Yumigeta, R. Sailus, M. Y. Sayyad, S. T. R. Moosavy, R. Kudrawiec, S. Tongay, Pressure-induced suppression of charge density phases across the entire rare-earth tritellurides by optical spectroscopy. J. Mater. Chem. C 10, 11995–12000 (2022)
2022
-
[33]
Lavagnini, M
M. Lavagnini, M. Baldini, A. Sacchetti, D. Di Castro, B. Delley, R. Monnier, J.-H. Chu, N. Ru, I. R. Fisher, P. Postorino, L. Degiorgi, Evidence for coupling between charge density waves and phonons in two-dimensional rare-earth tritellurides. Phys. Rev. B 78, 201101 (2008)
2008
-
[34]
Lazarević, Z
N. Lazarević, Z. V. Popović, R. Hu, C. Petrovic, Evidence of coupling between phonons and charge-density waves in ErTe 3. Phys. Rev. B 83, 024302 (2011)
2011
-
[35]
Samnakay, D
R. Samnakay, D. Wickramaratne, T. R. Pope, R. K. Lake, T. T. Salguero, A. A. Balandin, Zone-Folded Phonons and the Commensurate–Incommensurate Charge-Density-Wave Transition in 1T-TaSe2 Thin Films. Nano Lett. 15, 2965–2973 (2015)
2015
-
[36]
R. M. Martin, G. Lucovsky, K. Helliwell, Intermolecular bonding and lattice dynamics of Se and Te. Phys. Rev. B 13, 1383–1395 (1976)
1976
-
[37]
Y. Du, G. Qiu, Y. Wang, M. Si, X. Xu, W. Wu, P. D. Ye, One-Dimensional van der Waals Material Tellurium: Raman Spectroscopy under Strain and Magneto-Transport. Nano Lett. 17, 3965–3973 (2017)
2017
-
[38]
F. J. Manjón, S. Gallego-Parra, P. Rodríguez-Hernández, A. Muñoz, C. Drasar, V. Muñoz- Sanjosé, O. Oeckler, Anomalous Raman modes in tellurides. J. Mater. Chem. C 9, 6277– 6289 (2021)
2021
-
[39]
M. A. Laguna, M. L. Sanjuán, A. Várez, J. Sanz, Lithium dynamics and disorder effects in the Raman spectrum of La ( 2 − x ) / 3 Li x TiO 3. Phys. Rev. B 66, 054301 (2002)
2002
-
[40]
Maschek, S
M. Maschek, S. Rosenkranz, R. Heid, A. H. Said, P. Giraldo-Gallo, I. R. Fisher, F. Weber, Wave-vector-dependent electron-phonon coupling and the charge-density-wave transition in TbT e 3. Phys. Rev. B 91, 235146 (2015)
2015
-
[41]
Weber, S
F. Weber, S. Rosenkranz, J.-P. Castellan, R. Osborn, G. Karapetrov, R. Hott, R. Heid, K.-P. Bohnen, A. Alatas, Electron-Phonon Coupling and the Soft Phonon Mode in TiSe 2. Phys. Rev. Lett. 107, 266401 (2011)
2011
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.