We have constructed a broadband ultrafast time-resolved infrared (TRIR) spectrometer and incorporated it into our existing time-resolved spectroscopy apparatus, thus creating a single instrument capable of performing the complementary techniques of femto-/picosecond time-resolved resonance Raman (TR3), fluorescence, and UV/visible/infrared transient absorption spectroscopy. The TRIR spectrometer employs broadband (150 fs, approximately 150 cm(-1) FWHM) mid-infrared probe and reference pulses (generated by difference frequency mixing of near-infrared pulses in type I AgGaS2), which are dispersed over two 64-element linear infrared array detectors (HgCdTe). These are coupled via custom-built data acquisition electronics to a personal computer for data processing. This data acquisition system performs signal handling on a shot-by-shot basis at the 1 kHz repetition rate of the pulsed laser system. The combination of real-time signal processing and the ability to normalize each probe and reference pulse has enabled us to achieve a high sensitivity on the order of deltaOD approximately 10(-4) - 10(-5) with 1 min of acquisition time. We present preliminary picosecond TRIR studies using this spectrometer and also demonstrate how a combination of TRIR and TR3 spectroscopy can provide key information for the full elucidation of a photochemical process.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1366/00037020360625899 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
A Cost-Effective Computational Strategy for the Electronic Layout Characterization of a Second Generation Light-Driven Molecular Rotary Motor in Solution.
J Comput Chem
January 2025
Scuola Superiore Meridionale, Napoli, Italy.
Light-driven molecular rotary motors are nanometric machines able to convert light into unidirectional motions. Several types of molecular motors have been developed to better respond to light stimuli, opening new avenues for developing smart materials ranging from nanomedicine to robotics. They have great importance in the scientific research across various disciplines, but a detailed comprehension of the underlying ultrafast photophysics immediately after photo-excitation, that is, Franck-Condon region characterization, is not fully achieved yet.
View Article and Find Full Text PDFA Complete Description of the Ultrafast Proton Transfer Dynamics in the Excited State of D-Luciferin.
J Phys Chem B
January 2025
UM-DAE Centre for Excellence in Basic Sciences, Kalina Campus of Mumbai University, Santacruz (E), Mumbai 400098, India.
Excited-state proton transfer (ESPT) in organic photoacids is a widely studied phenomenon in which D-luciferin is of special mention, considering the fact that apart from its phenolic OH group, the nitrogen atoms at either of the two thiazole moieties could also participate in hydrogen bonding interactions with a proton-donating solvent during ESPT. As a result, several transient species could appear during the ESPT process. We hereby deploy subpicosecond time-resolved fluorescence upconversion (FLUP) and transient absorption (TA) spectroscopic techniques to understand the detailed photophysics of D-luciferin in water as well as in dimethyl sulfoxide (DMSO) and ethanol.
View Article and Find Full Text PDFUltrastructural membrane dynamics of mouse and human cortical synapses.
bioRxiv
December 2024
Department of Cell Biology, The Johns Hopkins University, Baltimore MD, 21205, USA.
Live human brain tissues provide unique opportunities for understanding the physiology and pathophysiology of synaptic transmission. Investigations have been limited to anatomy, electrophysiology, and protein localization-while crucial parameters such as synaptic vesicle dynamics were not visualized. Here we utilize zap-and-freeze time-resolved electron microscopy to overcome this hurdle.
View Article and Find Full Text PDFTerahertz Saturable Absorption across Charge Separation in Photoexcited Monolayer Graphene/MoS Heterostructure.
J Phys Chem Lett
January 2025
Key Laboratory of Materials Physics, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei 230031, China.
Unveiling the nonlinear interactions between terahertz (THz) electromagnetic waves and free carriers in two-dimensional materials is crucial for the development of high-field and high-frequency electronic devices. Herein, we investigate THz nonlinear transport dynamics in a monolayer graphene/MoS heterostructure using time-resolved THz spectroscopy with intense THz pulses as the probe. Following ultrafast photoexcitation, the interfacial charge transfer establishes a nonequilibrium carrier redistribution, leaving free holes in the graphene and trapping electrons in the MoS.
View Article and Find Full Text PDFAn ultrafast algorithm for ultrafast time-resolved coherent Raman spectroscopy.
Commun Chem
January 2025
Energy & Materials Transition, Netherlands Organization for Applied Scientific Research (TNO), Urmonderbaan 22, Geleen, 6167RD, The Netherlands.
Time-resolved coherent Raman spectroscopy (CRS) is a powerful non-linear optical technique for quantitative, in-situ analysis of chemically reacting flows, offering unparalleled accuracy and exceptional spatiotemporal resolution. Its application to large polyatomic molecules, crucial for understanding reaction dynamics, has thus far been limited by the complexity of their rotational-vibrational Raman spectra. Progress in developing comprehensive spectral codes for these molecules, a longstanding goal, has been hindered by prohibitively long computation times required for their spectral synthesis.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!