Quantum dynamical simulations of vibrational spectroscopy have been carried out for glycine dipeptide (CH(3)-CO-NH-CH(2)-CO-NH-CH(3)). Conformational structure and dynamics are modeled in terms of the two Ramachandran dihedral angles of the molecular backbone. Potential energy surfaces and harmonic frequencies are obtained from electronic structure calculations at the density functional theory ...

We report a photodetachment and high-resolution photoelectron imaging study of cold 2-hydroxyphenoxide anion, o - HO(C6H4)O(-), cooled in a cryogenic ion trap. Photodetachment spectroscopy revealed a dipole-bound state (DBS) of the anion, 25 ± 5 cm(-1), below the detachment threshold of 18 784 ± 5 cm−1 (2.3289 ± 0.0006 eV), i.e., the electron affinity of the 2-hydroxyphenoxy radical o - HO(C6H4...

Enantioenriched square-pyramidal oxo- and sulfidorhenium(v) complexes have been prepared and their stereochemistry studied by vibrational circular dichroism (VCD) spectroscopy.

Using p-aminothiophenol (PATP) molecules on a gold substrate and high-vacuum tip-enhanced Raman spectroscopy (HV-TERS), we show that the vibrational spectra of these molecules are distinctly different from those in typical surface-enhanced Raman spectroscopy. Detailed first-principles calculations help to assign the Raman peaks in the TERS measurements as Raman-active and IR-active vibrational ...

We have studied the carbonate mineral kamphaugite-(Y)(CaY(CO3)2(OH)·H2O), a mineral which contains yttrium and specific rare earth elements. Chemical analysis shows the presence of Ca, Y and C. Back scattering SEM appears to indicate a single pure phase. The vibrational spectroscopy of kamphaugite-(Y) was obtained using a combination of Raman and infrared spectroscopy. Two distinct Raman bands ...

Quantitative vibrational difference spectroscopy of small signals requires techniques that minimize spectral noise. As simple modulation of the sample followed by signal demodulation is often problematic due to interference with the FT-IR Fourier frequencies, alternate methods are necessary. Using vibrational Stark spectroscopy as an example, the DC method involves alternating complete interfer...

We report an investigation of Raman spectroscopy on the structure of As40SxSe60-x glasses prepared by conventional melt-quenching techniques with As, S and Se of 99.99% purity. And vibrational modes of AsSnSe3-n clusters were calculated by Gaussian software based on Density functional theory (DFT). It can be found that the calculated data of basic cluster models are in excellent agreement with ...