{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,7]],"date-time":"2026-08-07T15:39:44Z","timestamp":1786117184260,"version":"build-2736575974"},"reference-count":34,"publisher":"American Chemical Society (ACS)","issue":"31","license":[{"start":{"date-parts":[[2026,7,28]],"date-time":"2026-07-28T00:00:00Z","timestamp":1785196800000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-029"},{"start":{"date-parts":[[2026,7,28]],"date-time":"2026-07-28T00:00:00Z","timestamp":1785196800000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-037"},{"start":{"date-parts":[[2026,7,28]],"date-time":"2026-07-28T00:00:00Z","timestamp":1785196800000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-045"}],"funder":[{"name":"Guangdong Major Project of Basic and Applied Basic Research","award":["2023B0303000002"],"award-info":[{"award-number":["2023B0303000002"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China (NSFC)","doi-asserted-by":"crossref","award":["22373046"],"award-info":[{"award-number":["22373046"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China (NSFC)","doi-asserted-by":"crossref","award":["224B2304"],"award-info":[{"award-number":["224B2304"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,8,6]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>While the exceptional emission properties of two-dimensional Ruddlesden\u2013Popper perovskites are fundamentally governed by exciton\u2013phonon interactions, tracking these dynamic lattice couplings remains elusive due to the state-filling limitations of visible-spectrum spectroscopy. Herein, we utilize broadband mid-infrared transient absorption spectroscopy to directly probe the intraexcitonic transitions and dynamic lattice reorganizations across a dimensionality series (n = 1, 2, and 4) of phenethylammonium (PEA)-based perovskites. We observe a profound, dimensionality-driven tuning of the microscopic coupling mechanism. In the extreme confinement limit (n = 1), intense structural distortion washes out discrete transitions, yielding a broad continuum indicative of rapid self-trapping. Relaxing this confinement (n = 2) unveils beautifully resolved Franck\u2013Condon progressions driven by \u224810 meV inorganic Pb\u2013I optical phonons. By fitting this progression, we extract a Huang\u2013Rhys factor of S \u2248 0.57, quantitatively confirming an intermediate coupling regime that prevents deep self-trapping. Further relaxation (n = 4) shifts the dominant interaction to higher-energy (\u224833 meV) organic cation modes. This work demonstrates that structural dimensionality provides a direct lever to engineer the specific exciton\u2013phonon bath, offering the fundamental physical blueprint required to optimize emission lineshapes for high-efficiency perovskite optoelectronics.<\/jats:p>","DOI":"10.1021\/acs.jpclett.6c01982","type":"journal-article","created":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T13:13:35Z","timestamp":1785849215000},"page":"8898-8904","source":"Crossref","is-referenced-by-count":0,"title":["Dimensionality-Dependent\nExciton\u2013Phonon Coupling\nin 2D and Quasi-2D Perovskites Revealed by Transient Infrared Spectroscopy"],"prefix":"10.1021","volume":"17","author":[{"given":"Shaokuan","family":"Gong","sequence":"first","affiliation":[{"name":"Southern University of Science and Technology , , , ,","place":["Shenzhen, China, 518055"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pan","family":"Wang","sequence":"additional","affiliation":[{"name":"Southern University of Science and Technology , , , ,","place":["Shenzhen, China, 518055"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuling","family":"Huang","sequence":"additional","affiliation":[{"name":"Southern University of Science and Technology , , , ,","place":["Shenzhen, China, 518055"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0252-3086","authenticated-orcid":true,"given":"Haipeng","family":"Lu","sequence":"additional","affiliation":[{"name":"The Hong Kong University of Science and Technology , , ,","place":["Hong Kong, China, 999077"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xihan","family":"Chen","sequence":"additional","affiliation":[{"name":"Southern University of Science and Technology , , , ,","place":["Shenzhen, China, 518055"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,7,28]]},"reference":[{"issue":"12","key":"2026080609081641600_cit1","doi-asserted-by":"publisher","first-page":"969","DOI":"10.1038\/s41565-020-00811-1","article-title":"Semiconductor physics of organic\u2013inorganic 2D\nhalide perovskites","volume":"15","author":"Blancon","year":"2020","journal-title":"Nat. Nanotechnol."},{"issue":"6534","key":"2026080609081641600_cit2","doi-asserted-by":"publisher","first-page":"1129","DOI":"10.1126\/science.abf5291","article-title":"Chiral-induced\nspin selectivity enables a room-temperature\nspin light-emitting diode","volume":"371","author":"Kim","year":"2021","journal-title":"Science"},{"issue":"9","key":"2026080609081641600_cit3","doi-asserted-by":"publisher","first-page":"528","DOI":"10.1038\/s41566-018-0220-6","article-title":"Spin control\nin reduced-dimensional chiral perovskites","volume":"12","author":"Long","year":"2018","journal-title":"Nat.\nPhotonics"},{"key":"2026080609081641600_cit4","doi-asserted-by":"publisher","DOI":"10.1093\/nsr\/nwae461","article-title":"Giant deformation potential induced small polaron\neffect\nin Dion\u2013Jacobson two-dimensional lead halide perovskites","volume":"12","author":"Huang","year":"2025","journal-title":"Natl. Sci. Rev."},{"issue":"10","key":"2026080609081641600_cit5","doi-asserted-by":"publisher","first-page":"3775","DOI":"10.1021\/jacs.8b00542","article-title":"Hybrid\nDion\u2013Jacobson 2D Lead Iodide Perovskites","volume":"140","author":"Mao","year":"2018","journal-title":"J. Am. Chem. Soc."},{"issue":"9","key":"2026080609081641600_cit6","doi-asserted-by":"publisher","first-page":"2273","DOI":"10.1021\/acsenergylett.8b01315","article-title":"Impact of Layer Thickness on the\nCharge Carrier and Spin Coherence Lifetime in Two-Dimensional Layered\nPerovskite Single Crystals","volume":"3","author":"Chen","year":"2018","journal-title":"ACS Energy Lett."},{"key":"2026080609081641600_cit7","doi-asserted-by":"publisher","first-page":"2378","DOI":"10.1021\/acs.jpclett.5c00119","article-title":"Quantification of Chirality Induced\nSpin\u2013Orbit Coupling for Long Spin Polarized Lifetime in Hybrid\nPerovskite","volume":"16","author":"Huang","year":"2025","journal-title":"J. Phys. Chem. Lett."},{"issue":"25","key":"2026080609081641600_cit8","doi-asserted-by":"publisher","DOI":"10.1103\/9tfy-gp2t","article-title":"Enhancing Hot-Carrier\nLifetime through\nSpin Splitting and Strain Interaction in Chiral Perovskite Materials","volume":"136","author":"Huang","year":"2026","journal-title":"Phys. Rev. Lett."},{"issue":"6331","key":"2026080609081641600_cit9","doi-asserted-by":"publisher","first-page":"1288","DOI":"10.1126\/science.aal4211","article-title":"Extremely\nefficient internal exciton dissociation\nthrough edge states in layered 2D perovskites","volume":"355","author":"Blancon","year":"2017","journal-title":"Science"},{"issue":"17","key":"2026080609081641600_cit10","doi-asserted-by":"publisher","first-page":"2999","DOI":"10.1021\/jz401532q","article-title":"Importance of Spin\u2013Orbit\nCoupling in Hybrid Organic\/Inorganic Perovskites for Photovoltaic\nApplications","volume":"4","author":"Even","year":"2013","journal-title":"J. Phys. Chem. Lett."},{"issue":"10","key":"2026080609081641600_cit11","doi-asserted-by":"publisher","first-page":"2595","DOI":"10.1021\/acs.jpclett.8b00526","article-title":"Excitonic Effects in Methylammonium\nLead Halide Perovskites","volume":"9","author":"Chen","year":"2018","journal-title":"J. Phys. Chem. Lett."},{"issue":"5","key":"2026080609081641600_cit12","doi-asserted-by":"publisher","first-page":"3140","DOI":"10.1021\/acs.chemrev.8b00417","article-title":"Quantum and Dielectric Confinement\nEffects in Lower-Dimensional Hybrid Perovskite Semiconductors","volume":"119","author":"Katan","year":"2019","journal-title":"Chem. Rev."},{"issue":"11","key":"2026080609081641600_cit13","doi-asserted-by":"publisher","first-page":"7001","DOI":"10.1021\/acs.nanolett.6b03114","article-title":"Charge-Carrier Dynamics in 2D Hybrid\nMetal\u2013Halide\nPerovskites","volume":"16","author":"Milot","year":"2016","journal-title":"Nano Lett."},{"issue":"1","key":"2026080609081641600_cit14","doi-asserted-by":"publisher","first-page":"8541","DOI":"10.1038\/s41467-024-52952-9","article-title":"Robust excitonic light emission in 2D tin halide perovskites\nby weak\nexcited state polaronic effect","volume":"15","author":"Zhou","year":"2024","journal-title":"Nat. Commun."},{"issue":"17","key":"2026080609081641600_cit15","doi-asserted-by":"publisher","first-page":"12225","DOI":"10.1021\/jacs.4c03532","article-title":"Tuning Spin-Polarized\nLifetime at High Carrier Density through Deformation Potential in\nDion\u2013Jacobson-Phase Perovskites","volume":"146","author":"Huang","year":"2024","journal-title":"J. Am.\nChem. Soc."},{"issue":"1","key":"2026080609081641600_cit16","doi-asserted-by":"publisher","first-page":"39","DOI":"10.1021\/jacs.6b10390","article-title":"Broadband Emission\nin Two-Dimensional Hybrid Perovskites: The Role of Structural Deformation","volume":"139","author":"Cortecchia","year":"2017","journal-title":"J. Am. Chem. Soc."},{"issue":"44","key":"2026080609081641600_cit17","doi-asserted-by":"publisher","first-page":"10046","DOI":"10.1021\/acs.jpclett.3c02346","article-title":"Correlated\nSelf-Trapped Excitons and Free Excitons with Intermediate\nExciton\u2013Phonon Coupling in 2D Mixed-Halide Perovskites","volume":"14","author":"Yang","year":"2023","journal-title":"J. Phys. Chem. Lett."},{"issue":"2","key":"2026080609081641600_cit18","doi-asserted-by":"publisher","first-page":"347","DOI":"10.1021\/acsenergylett.9b02490","article-title":"Origin of Broad-Band\nEmission and\nImpact of Structural Dimensionality in Tin-Alloyed Ruddlesden\u2013Popper\nHybrid Lead Iodide Perovskites","volume":"5","author":"Li","year":"2020","journal-title":"ACS Energy Lett."},{"issue":"7726","key":"2026080609081641600_cit19","doi-asserted-by":"publisher","first-page":"245","DOI":"10.1038\/s41586-018-0575-3","article-title":"Perovskite\nlight-emitting\ndiodes with external quantum efficiency exceeding 20%","volume":"562","author":"Lin","year":"2018","journal-title":"Nature"},{"issue":"11","key":"2026080609081641600_cit20","doi-asserted-by":"publisher","first-page":"5370","DOI":"10.1021\/acs.chemmater.4c00015","article-title":"Tailoring\nPure-Phase Quasi-2D Perovskites\nvia the Polymer Crystallization-Assisted Strategy","volume":"36","author":"Liu","year":"2024","journal-title":"Chem. Mater."},{"issue":"12","key":"2026080609081641600_cit21","doi-asserted-by":"publisher","first-page":"7061","DOI":"10.1021\/acs.jpcc.9b00555","article-title":"Vibrational Probe of the Structural\nOrigins of Slow\nRecombination in Halide Perovskites","volume":"123","author":"Munson","year":"2019","journal-title":"J. Phys.\nChem. C"},{"issue":"32","key":"2026080609081641600_cit22","doi-asserted-by":"publisher","DOI":"10.1002\/adfm.202300363","article-title":"Exciton\nFormation Dynamics and Band-Like Free Charge-Carrier Transport in\n2D Metal Halide Perovskite Semiconductors","volume":"33","author":"Motti","year":"2023","journal-title":"Adv.\nFunct. Mater."},{"issue":"3","key":"2026080609081641600_cit23","doi-asserted-by":"publisher","first-page":"3312","DOI":"10.1021\/acsnano.4c12035","article-title":"Photoinduced Fro\u0308hlich\nInteraction-Driven Distinct\nElectron- and Hole-Polaron Behaviors in Hybrid Organic\u2013Inorganic\nPerovskites by Ultrafast Terahertz Probes","volume":"19","author":"Song","year":"2025","journal-title":"ACS\nNano"},{"issue":"30","key":"2026080609081641600_cit24","doi-asserted-by":"publisher","first-page":"16399","DOI":"10.1039\/C9CP02768H","article-title":"Ultrafast probes at the interfaces\nof solar energy conversion materials","volume":"21","author":"Chen","year":"2019","journal-title":"Phys.\nChem. Chem. Phys."},{"issue":"3","key":"2026080609081641600_cit25","doi-asserted-by":"publisher","first-page":"1455","DOI":"10.1021\/acs.nanolett.6b04422","article-title":"Direct Observation of Ultrafast Exciton Formation in a Monolayer\nof WSe2","volume":"17","author":"Steinleitner","year":"2017","journal-title":"Nano Lett."},{"issue":"45","key":"2026080609081641600_cit26","doi-asserted-by":"publisher","first-page":"41845","DOI":"10.1021\/jacs.5c14647","article-title":"Mechanistic Insight into Tunable\nSpin Relaxation in Two-Dimensional\nType-II Ligand-Perovskite Heterostructures","volume":"147","author":"Soni","year":"2025","journal-title":"J. Am. Chem. Soc."},{"issue":"23","key":"2026080609081641600_cit27","doi-asserted-by":"publisher","DOI":"10.1103\/xt4h-qgg3","article-title":"Electron-phonon\ncoupling mediated by Frohlich interaction in perovskite Rb2SnBr6","volume":"112","author":"Soares","year":"2025","journal-title":"Phys. Rev. B"},{"issue":"45","key":"2026080609081641600_cit28","doi-asserted-by":"publisher","first-page":"19128","DOI":"10.1021\/jacs.1c08900","article-title":"Ultrafast\nand High-Yield Polaronic\nExciton Dissociation in Two-Dimensional Perovskites","volume":"143","author":"Sun","year":"2021","journal-title":"J. Am. Chem. Soc."},{"issue":"24","key":"2026080609081641600_cit29","doi-asserted-by":"publisher","first-page":"9123","DOI":"10.1021\/jacs.1c03064","article-title":"Giant Huang\u2013Rhys\nFactor for Electron Capture by the Iodine\nIntersitial in Perovskite Solar Cells","volume":"143","author":"Whalley","year":"2021","journal-title":"J. Am.\nChem. Soc."},{"issue":"7","key":"2026080609081641600_cit30","doi-asserted-by":"publisher","DOI":"10.1002\/advs.202305182","article-title":"Polaron Vibronic Progression\nShapes the Optical Response of 2D Perovskites","volume":"11","author":"Dyksik","year":"2024","journal-title":"Adv. Sci."},{"issue":"1","key":"2026080609081641600_cit31","doi-asserted-by":"publisher","first-page":"1833","DOI":"10.1038\/s41467-026-68545-7","article-title":"Regulating\nPb off-centering distortion for white-light emission in 2D halide\nperovskites","volume":"17","author":"Zhang","year":"2026","journal-title":"Nat. Commun."},{"issue":"24","key":"2026080609081641600_cit32","doi-asserted-by":"publisher","first-page":"11040","DOI":"10.1063\/1.1575735","article-title":"Spectroscopy and\ndynamics of methylamine. II. Rotational and vibrational structures\nof CH3NH2 and CH3ND2 in cationic D states","volume":"118","author":"Baek","year":"2003","journal-title":"J.\nChem. Phys."},{"issue":"15","key":"2026080609081641600_cit33","doi-asserted-by":"publisher","first-page":"5830","DOI":"10.1021\/acs.jpclett.0c01714","article-title":"Revealing Excitonic Phonon Coupling in (PEA)2(MA)n\u20131PbnI3n+1\n2D Layered Perovskites","volume":"11","author":"Urban","year":"2020","journal-title":"J. Phys. Chem. Lett."},{"issue":"17","key":"2026080609081641600_cit34","doi-asserted-by":"publisher","first-page":"10771","DOI":"10.1039\/D4NR04748F","article-title":"Exciton\u2013phonon\ncoupling in quasi-two-dimensional Ruddlesden\u2013Popper perovskites:\nimpact of a mixed-phase structure","volume":"17","author":"Sarkar","year":"2025","journal-title":"Nanoscale"}],"container-title":["The Journal of Physical\nChemistry Letters"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pubs.acs.org\/doi\/pdf\/10.1021\/acs.jpclett.6c01982","content-type":"application\/pdf","content-version":"vor","intended-application":"unspecified"},{"URL":"https:\/\/pubs.acs.org\/jpclcd\/article-pdf\/17\/31\/8898\/66318072\/acs.jpclett.6c01982.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/pubs.acs.org\/jpclcd\/article-pdf\/17\/31\/8898\/66318072\/acs.jpclett.6c01982.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,6]],"date-time":"2026-08-06T13:23:22Z","timestamp":1786022602000},"score":1,"resource":{"primary":{"URL":"https:\/\/pubs.acs.org\/jpclcd\/article\/17\/31\/8898\/5236060\/Dimensionality-Dependent-Exciton-Phonon-Coupling"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,7,28]]},"references-count":34,"journal-issue":{"issue":"31","published-online":{"date-parts":[[2026,7,28]]},"published-print":{"date-parts":[[2026,8,6]]}},"URL":"https:\/\/doi.org\/10.1021\/acs.jpclett.6c01982","relation":{},"ISSN":["1948-7185"],"issn-type":[{"value":"1948-7185","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,7,28]]}}}