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Title: Vibrational Sum-Frequency Generation Hyperspectral Microscopy for Molecular Self-Assembled Systems
In this review, we discuss the recent developments and applications of vibrational sum-frequency generation (VSFG) microscopy. This hyperspectral imaging technique can resolve systems without inversion symmetry, such as surfaces, interfaces and noncentrosymmetric self-assembled materials, in the spatial, temporal, and spectral domains. We discuss two common VSFG microscopy geometries: wide-field and confocal point-scanning. We then introduce the principle of VSFG and the relationships between hyperspectral imaging with traditional spectroscopy, microscopy, and time-resolved measurements. We further highlight crucial applications of VSFG microscopy in self-assembled monolayers, cellulose in plants, collagen fibers, and lattice self-assembled biomimetic materials. In these systems, VSFG microscopy reveals relationships between physical properties that would otherwise be hidden without being spectrally, spatially, and temporally resolved. Lastly, we discuss the recent development of ultrafast transient VSFG microscopy, which can spatially measure the ultrafast vibrational dynamics of self-assembled materials. The review ends with an outlook on the technical challenges of and scientific potential for VSFG microscopy.  more » « less
Award ID(s):
1828666
PAR ID:
10289341
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Annual Review of Physical Chemistry
Volume:
72
Issue:
1
ISSN:
0066-426X
Page Range / eLocation ID:
279 to 306
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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