BoxCARS 2D IR spectroscopy with pulse shaping

Al-Mualem, Ziareena; Chen, Xiaobing; Shirley, Joseph; Xu, Cong; Baiz, Carlos R.

doi:10.1364/oe.471984

Cited by 4 publications

(2 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The resulting spectrum correlates the excitation and detection frequency as a function of waiting time. The optical setup used is a pump-probe geometry which has been modified from the previously described optical setup, 47 and the measurement and data processing workflow has been described previously. 48 Here the spacing between pump pulse pairs was scanned between 0 fs and 4000 fs in steps of 20 fs using an acousto-optic modulator.…”

Section: B Two-dimensional Infrared Spectroscopymentioning

confidence: 99%

Experimental Two-Dimensional Infrared Spectra of Methyl Thiocyanate in Water and Organic Solvents

Shirley,

Baiz

2023

Preprint

View full text Add to dashboard Cite

Thiocyanates, nitriles, and azides represent a versatile set of vibrational probes to measure structure and dynamics in biological systems. The probes are minimally perturbative, the nitrile stretching mode appears in an otherwise uncongested spectral region, and the spectra report on the local environment around the probe. Nitrile frequencies and lineshapes, however, are difficult to interpret, and theoretical models that connect local environments with vibrational frequencies are often necessary. However, the development of both more accurate and intuitive models remains a challenge for the community. The present work provides an experimentally consistent collection of experimental measurements, including IR absorption and ultrafast two-dimensional infrared (2D IR) spectra, to serve as a benchmark in the development of future models. Specifically, we catalog spectra of the nitrile stretching mode of methyl thiocyanate (MeSCN) in fourteen different solvents including non-polar, polar, and protic solvents. Absorption spectra indicate that π interactions may be responsible for observed lineshape differences between aromatic and aliphatic alcohols. We also demonstrate that a recent Kamlet-Taft formulation describes the center frequency MeSCN. Further, we report cryogenic infrared spectra that may lead to insights into the peak asymmetry in aprotic solvents. 2D IR spectra measured in protic solvents serve to connect hydrogen bonding to static inhomogeneity. We expect that these insights, along with the publicly available dataset, will be useful to continue advancing future models capable of quantitatively describing the relation between local environments, lineshapes, and dynamics in nitrile probes.

show abstract

Section: B Two-dimensional Infrared Spectroscopymentioning

confidence: 99%

Experimental Two-Dimensional Infrared Spectra of Methyl Thiocyanate in Water and Organic Solvents

Shirley,

Baiz

2023

Preprint

View full text Add to dashboard Cite

show abstract

“…Illustration of pump-probe geometry is adapted from Fig. 1 of the cited publication 104 (10.1364/OE.471984, open access articles ⓒ 2023 Optica Publishing Group). The color scheme in this illustration has been adjusted to harmonize with the current figure.…”

Section: Introductionmentioning

confidence: 99%

Crowding alters F-actin secondary structure and hydration

Chen,

Roeters,

Cavanna

et al. 2023

Commun Biol

Self Cite

View full text Add to dashboard Cite

Actin, an important component of eukaryotic cell cytoskeleton, regulates cell shape and transport. The morphology and biochemical properties of actin filaments are determined by their structure and protein-protein contacts. Crowded environments can organize filaments into bundles, but less is known about how they affect F-actin structure. This study used 2D IR spectroscopy and spectral calculations to examine how crowding and bundling impact the secondary structure and local environments in filaments and weakly or strongly bundled networks. The results reveal that bundling induces changes in actin’s secondary structure, leading to a decrease in β-sheet and an increase in loop conformations. Strongly bundled networks exhibit a decrease in backbone solvent exposure, with less perturbed α-helices and nearly “locked” β-sheets. Similarly, the loops become less hydrated but maintain a dynamic environment. These findings highlight the role of loop structure in actin network morphology and stability under morphology control by PEG.

show abstract