Speaker
Description
Introduction
Temperature-driven phase transformations in crystalline materials strongly influence their structural stability and functional behavior. Conventional infrared spectroscopy often fails to resolve overlapping vibrational signals associated with these changes. To address this, two-dimensional infrared correlation spectroscopy (2D-IRCOS) was employed to enhance spectral resolution and reveal molecular-level dynamics during thermal transitions.
Method
Crystalline samples were subjected to controlled temperature variations while collecting IR spectra across a defined thermal range. The resulting spectral data were processed using Noda’s generalized 2D correlation approach to construct synchronous and asynchronous correlation maps, enabling detailed analysis of correlated and sequential molecular motions.
Results
The 2D-IRCOS analysis resolved overlapping vibrational bands and identified distinct stages of phase transformation. Synchronous maps revealed correlated intensity changes among key lattice and intermolecular modes, while asynchronous maps exposed the sequential order of structural rearrangements. These results confirmed that the phase transition involved both cooperative and stepwise molecular reorganizations.
Conclusion
2D-IRCOS proved highly effective in uncovering hidden spectral features and revealing the molecular mechanisms driving polymorphic transitions. This technique provides valuable insight into how temperature influences intermolecular interactions and lattice dynamics, offering a powerful framework for understanding and controlling the stability of crystalline materials.
