Structural dynamics of low-dimensional lead-free azetidinium metal halides: a Raman spectroscopic study

Abstract

Lead-free hybrid metal halides have been attracting attention for their potential in various optoelectronic applications due to their appropriate bandgap, ease of fabrication, and bandgap tunability. Recently, several low-dimensional lead-free azetidinium metal halides have been successfully synthesized. The fundamental nature of the phase transitions in these materials arises from the intermolecular dynamics of the inorganic octahedral framework and the orientation of the A-site cations. In this study, we performed temperature-dependent Raman spectroscopy on eight different lead-free azetidinium metal halides to investigate the correlation between vibrational energy shifts and structural phase transitions. We utilized 785 nm laser excitation to characterize the [BX 6 ] octahedral modes and observed distinct anomalies at the phase transition temperatures in select compounds. The 532 nm laser excitation wavelength was used to detect azetidinium vibrational modes. Although direct tracking of ring puckering and deformation modes was limited by weak signals, analysis of the temperature dependence of the CH 2 mode revealed a second-order transition driven by the azetidinium cations. Moreover, the observed intensity variations provided strong evidence for an order-disorder transition associated with the azetidinium dynamics. These results underscore the critical role of azetidinium molecular behavior in mediating phase transitions in hybrid halide systems.

Valley- and Spin-Dependent Electronic and Transport Properties of Two-Dimensional Altermagnetic Titanium-Based Chalcogenide Halides
Ruo-Yu Ning, Zhi-Hua Yan, Jin-Yang Li +2
arXiv14 Sep 2026PreprintarXiv licenceFull textCondensed matterarXiv
Structural, electronic, spectroscopic, and thermodynamic properties of gentisic acid: solvent and temperature effects using DFT and TD-DFT approaches
Eshetu Diriba Kena, Alemu Kebede Hordofa, Dereje Gelanu Dadi +2
Scientific Reports4 Oct 2026Peer-reviewedCC BY-NC-ND 4.0Full textAtomic, molecular & optical physicsCrossref
Three-dimensional dopant distribution from a single, out-of-focus spectroscopic image
Michael Deimetry, Timothy Petersen, Matthew Weyland +1
arXiv8 Oct 2026PreprintarXiv licenceFull textCondensed matterarXiv
Spectroscopic and Structural Properties of B, B_s, and B_c Mesons within a Non-Relativistic Potential Model: A Comparative Analysis via Matrix Numerov and Variational Methods
Pritom Kumar Nath, Rishan Dev Choudhury, Jugal Lahkar
arXiv14 Sep 2026PreprintarXiv licenceFull textHigh-energy & particle physicsarXiv
Spectroscopic study of the tunneling dynamics in N2-water observed in the O–D stretch region
R. Glorieux, C. Lauzin, A. J. Barclay +2
The Journal of Chemical Physics9 Oct 2026Peer-reviewedLicence not stated2 citedPhysical chemistry General physicsHAL

Cite

BibTeX RIS

BibTeX

@article{jin2026structural,
  title = {{Structural dynamics of low-dimensional lead-free azetidinium metal halides: a Raman spectroscopic study}},
  author = {Young Un Jin and Pascale Gemeiner and Bernd Marler and Marianela Escobar-Castillo and Andrei Salak and Brahim Dkhil and Niels Benson and Doru Lupascu},
  journal = {Physica Scripta},
  year = {2026},
  month = jul,
  doi = {10.1088/1402-4896/ae87df},
  url = {https://hal.science/hal-05748943v1},
  note = {CC BY},
}

RIS

TY  - JOUR
TI  - Structural dynamics of low-dimensional lead-free azetidinium metal halides: a Raman spectroscopic study
AU  - Young Un Jin
AU  - Pascale Gemeiner
AU  - Bernd Marler
AU  - Marianela Escobar-Castillo
AU  - Andrei Salak
AU  - Brahim Dkhil
AU  - Niels Benson
AU  - Doru Lupascu
PY  - 2026
DA  - 2026/07/23
JO  - Physica Scripta
DO  - 10.1088/1402-4896/ae87df
UR  - https://hal.science/hal-05748943v1
AB  - Lead-free hybrid metal halides have been attracting attention for their potential in various optoelectronic applications due to their appropriate bandgap, ease of fabrication, and bandgap tunability. Recently, several low-dimensional lead-free azetidinium metal halides have been successfully synthesized. The fundamental nature of the phase transitions in these materials arises from the intermolecular dynamics of the inorganic octahedral framework and the orientation of the A-site cations. In this study, we performed temperature-dependent Raman spectroscopy on eight different lead-free azetidinium metal halides to investigate the correlation between vibrational energy shifts and structural phase transitions. We utilized 785 nm laser excitation to characterize the [BX 6 ] octahedral modes and observed distinct anomalies at the phase transition temperatures in select compounds. The 532 nm laser excitation wavelength was used to detect azetidinium vibrational modes. Although direct tracking of ring puckering and deformation modes was limited by weak signals, analysis of the temperature dependence of the CH 2 mode revealed a second-order transition driven by the azetidinium cations. Moreover, the observed intensity variations provided strong evidence for an order-disorder transition associated with the azetidinium dynamics. These results underscore the critical role of azetidinium molecular behavior in mediating phase transitions in hybrid halide systems.
SN  - 0031-8949
SN  - 1402-4896
ER  -

Abstract

Related

Cite