001037544 001__ 1037544 001037544 005__ 20250610131443.0 001037544 0247_ $$2doi$$a10.1038/s41567-024-02707-6 001037544 0247_ $$2ISSN$$a1745-2473 001037544 0247_ $$2ISSN$$a1745-2481 001037544 0247_ $$2WOS$$aWOS:001390246300001 001037544 037__ $$aFZJ-2025-00733 001037544 082__ $$a530 001037544 1001_ $$0P:(DE-HGF)0$$aDing, Jingxuan$$b0 001037544 245__ $$aLiquid-like dynamics in a solid-state lithium electrolyte 001037544 260__ $$aBasingstoke$$bNature Publishing Group$$c2025 001037544 3367_ $$2DRIVER$$aarticle 001037544 3367_ $$2DataCite$$aOutput Types/Journal article 001037544 3367_ $$0PUB:(DE-HGF)16$$2PUB:(DE-HGF)$$aJournal Article$$bjournal$$mjournal$$s1747803498_26766 001037544 3367_ $$2BibTeX$$aARTICLE 001037544 3367_ $$2ORCID$$aJOURNAL_ARTICLE 001037544 3367_ $$00$$2EndNote$$aJournal Article 001037544 520__ $$aSuperionic materials represent a regime intermediate between the crystalline and liquid states of matter. Despite the considerable interest in potential applications for solid-state batteries or thermoelectric devices, it remains unclear whether the fast ionic diffusion observed in superionic materials reflects liquid-like dynamics or whether the hops of mobile ions are inherently coupled to more conventional lattice phonons. Here we reveal a crossover from crystalline vibrations to relaxational dynamics of ionic diffusion in the superionic compound $Li_6PS_5Cl$, a candidate solid-state electrolyte. By combining inelastic and quasi-elastic neutron-scattering measurements with first-principles-based machine-learned molecular dynamics simulations, we found that the vibrational density of states in the superionic state strongly deviates from the quadratic behaviour expected from the Debye law of lattice dynamics. The superionic dynamics emerges from overdamped phonon quasiparticles to give rise to a linear density of states characteristic of instantaneous normal modes in the liquid state. Further, we showed that the coupling of lattice phonons with a dynamic breathing of the $Li^+$ diffusion bottleneck enables an order-of-magnitude increase in diffusivity. Thus, our results shed insights into superionics for future energy storage and conversion technologies. 001037544 536__ $$0G:(DE-HGF)POF4-1221$$a1221 - Fundamentals and Materials (POF4-122)$$cPOF4-122$$fPOF IV$$x0 001037544 588__ $$aDataset connected to CrossRef, Journals: juser.fz-juelich.de 001037544 7001_ $$00000-0002-9016-2438$$aGupta, Mayanak K.$$b1 001037544 7001_ $$0P:(DE-HGF)0$$aRosenbach, Carolin$$b2 001037544 7001_ $$00000-0002-3693-3668$$aLin, Hung-Min$$b3 001037544 7001_ $$00000-0002-0213-2299$$aOsti, Naresh C.$$b4 001037544 7001_ $$00000-0002-3533-003X$$aAbernathy, Douglas L.$$b5 001037544 7001_ $$0P:(DE-Juel1)184735$$aZeier, Wolfgang$$b6$$ufzj 001037544 7001_ $$0P:(DE-HGF)0$$aDelaire, Olivier$$b7$$eCorresponding author 001037544 773__ $$0PERI:(DE-600)2206346-8$$a10.1038/s41567-024-02707-6$$p118–125$$tNature physics$$v21$$x1745-2473$$y2025 001037544 8564_ $$uhttps://juser.fz-juelich.de/record/1037544/files/s41567-024-02707-6.pdf$$yRestricted 001037544 909CO $$ooai:juser.fz-juelich.de:1037544$$pVDB 001037544 9101_ $$0I:(DE-588b)5008462-8$$6P:(DE-Juel1)184735$$aForschungszentrum Jülich$$b6$$kFZJ 001037544 9131_ $$0G:(DE-HGF)POF4-122$$1G:(DE-HGF)POF4-120$$2G:(DE-HGF)POF4-100$$3G:(DE-HGF)POF4$$4G:(DE-HGF)POF$$9G:(DE-HGF)POF4-1221$$aDE-HGF$$bForschungsbereich Energie$$lMaterialien und Technologien für die Energiewende (MTET)$$vElektrochemische Energiespeicherung$$x0 001037544 9141_ $$y2025 001037544 915__ $$0StatID:(DE-HGF)0420$$2StatID$$aNationallizenz$$d2024-12-11$$wger 001037544 915__ $$0StatID:(DE-HGF)3003$$2StatID$$aDEAL Nature$$d2024-12-11$$wger 001037544 915__ $$0StatID:(DE-HGF)0100$$2StatID$$aJCR$$bNAT PHYS : 2022$$d2024-12-11 001037544 915__ $$0StatID:(DE-HGF)0200$$2StatID$$aDBCoverage$$bSCOPUS$$d2024-12-11 001037544 915__ $$0StatID:(DE-HGF)0300$$2StatID$$aDBCoverage$$bMedline$$d2024-12-11 001037544 915__ $$0StatID:(DE-HGF)0600$$2StatID$$aDBCoverage$$bEbsco Academic Search$$d2024-12-11 001037544 915__ $$0StatID:(DE-HGF)0030$$2StatID$$aPeer Review$$bASC$$d2024-12-11 001037544 915__ $$0StatID:(DE-HGF)0199$$2StatID$$aDBCoverage$$bClarivate Analytics Master Journal List$$d2024-12-11 001037544 915__ $$0StatID:(DE-HGF)1150$$2StatID$$aDBCoverage$$bCurrent Contents - Physical, Chemical and Earth Sciences$$d2024-12-11 001037544 915__ $$0StatID:(DE-HGF)0160$$2StatID$$aDBCoverage$$bEssential Science Indicators$$d2024-12-11 001037544 915__ $$0StatID:(DE-HGF)0113$$2StatID$$aWoS$$bScience Citation Index Expanded$$d2024-12-11 001037544 915__ $$0StatID:(DE-HGF)0150$$2StatID$$aDBCoverage$$bWeb of Science Core Collection$$d2024-12-11 001037544 915__ $$0StatID:(DE-HGF)9915$$2StatID$$aIF >= 15$$bNAT PHYS : 2022$$d2024-12-11 001037544 920__ $$lno 001037544 9201_ $$0I:(DE-Juel1)IMD-4-20141217$$kIMD-4$$lHelmholtz-Institut Münster Ionenleiter für Energiespeicher$$x0 001037544 980__ $$ajournal 001037544 980__ $$aVDB 001037544 980__ $$aI:(DE-Juel1)IMD-4-20141217 001037544 980__ $$aUNRESTRICTED