We describe a microscope for measuring two-dimensional infrared (2D IR) spectra of heterogeneous samples with μm-scale spatial resolution, sub-picosecond time resolution, and the molecular structure information of 2D IR, enabling the measurement of vibrational dynamics through correlations in frequency, time, and space. The setup is based on a fully collinear "one beam" geometry in which all pu...

Ultrafast two dimensional infrared (2D IR) spectroscopy has been applied to probe the intermolecular vibrational energy exchange between two model molecules, benzonitrile and acetonitrile-(d3). The vibrational energy exchange between these two molecules is manifested through the growth of cross peaks in their 2D IR spectra. In experiments, their nitrile groups (CN) are not involved in the energ...

Theoretical calculations at the B3LYP/aug-cc-pVQZ level are performed on ternary clusters of water, hydrogen chloride and nitric acid to predict their IR and MW spectra. The main IR spectral features and their changes in a set of 15 selected clusters are analyzed in terms of the different hydrogen bonding characteristics of the aggregates. The formation of these clusters in laboratory experimen...

The monazite-type solid solution of LaPO4 and EuPO4 has been studied by X-ray diffraction, infrared (IR) and Raman spectroscopic techniques. A substantial excessmolar volume has been derived from the X-ray data, and the Raman and IR spectra show band broadening typical for mixing of cations of different size on the cation sublattice. The IR spectra were interpreted by the autocorrelation method...

The combination of conformation selective far-IR/UV double resonance spectroscopy with Born-Oppenheimer molecular dynamics (BOMD) simulations is presented here for the structural characterization of the Ac-Phe-Pro-NH2 peptide in the far-infrared spectral domain, i.e. for radiation below 800 cm(-1). Two conformers have been shown to be present in the experiment, namely a conformer with a γ-turn ...

The strong coupling between two autoionizing states in helium is studied theoretically with the pump-probe scheme. An isolated 100-as XUV pulse is used to excite helium near the 2s2p(1 P ) resonance state in the presence of an intense infrared (IR) laser. The laser field introduces strong coupling between 2s2p(1 P ) and 2p2(1 S) states. The IR also can ionize helium from both autoionizing state...

The vibrational motion of a molecule is quantized and the resulting energy level spacings give rise to transitions in the mid-IR portion of the electromagnetic spectrum (4000 to ca. 400 cm). As you know from study of the diatomic harmonic oscillator, the energies (or wavenumber positions, cm) of these transitions are related to the bond strength (force constant), bond length, and atomic masses ...

Mid-infrared (IR) spectra of a series of calcium silicate hydrates (C-S-H) gels synthesised from C3S in the presence of magnesium oxide show many similarities with the mid-IR spectra of pure C-S-H gels. However, the presence of the vibration bands attributed to brucite is observed in all spectra of C-S-H synthesised with MgO, although only the sample with the highest CaO/SiO2 ratio (1.8) reveal...

An infrared spectrum recorded from a microscopic sample depends on spectral properties of the constituent material as well as on morphology. Many samples or domains within heterogeneous materials can be idealized as spheres, in which both scattering and absorption from the three-dimensional shape affect the recorded spectrum. Spectra recorded from such objects may be altered to such an extent t...

The photocatalytic degradation of dye Rhodamine B (RhB) in the presence of TiO2 nanostripe or P25 under visible light irradiation was investigated. The degradation intermediates were identified using Infrared spectra (IR spectra), 1H nuclear magnetic resonance (1HNMR) spectra, and gas chromatography-mass spectroscopy (GC-MS). The IR and the 1HNMR results showed that the large conjugated chromop...