Low-Frequency CH Stretch Vibrations of Free Alkoxide Ions

Anharmonic coupling of the CH-stretch and CH-bend vibrations of chloroform as studied by near-infrared electroabsorption spectroscopy.

Combination bands that involve CH- or OH-stretch vibrations appear in the near-infrared (NIR) region (4000-10 000 cm(-1)). Because they arise from anharmonic coupling between the component fundamentals, detailed analysis of the frequency and intensity of NIR combination bands allows one to elucidate the mechanisms behind the vibrational coupling in the condensed phase in terms of mechanical and...

Vibrations of low frequency over the precordium.

A method for taking tracings which represent actual movements of the precordium (displacement curves) or records which show waves proportional to the velocity of movement of the chest wall (velocity curves) is described. The equipment employed is readily available, and the method is easy to use. The displacement curves are nearly identical with cardiograms taken with a good optical setup, and t...

Low-frequency vibrations of DNA molecules.

A model for calculating the low-frequency modes in DNA molecules is presented. The present model is associated with the 'breathing' of a DNA molecule as well as its complementary hydrogen bonds. The calculated results show excellent agreement with the observed low-frequency wavenumber (30 cm-1). Consequently, such an internal motion as reflected in the proposed model might be the origin of the ...

Low-frequency vibrations of soft colloidal glasses.

We conduct experiments on two-dimensional packings of colloidal thermosensitive hydrogel particles whose packing fraction can be tuned above the jamming transition by varying the temperature. By measuring displacement correlations between particles, we extract the vibrational properties of a corresponding "shadow" system with the same configuration and interactions, but for which the dynamics o...

MEMS Energy Harvesting from Low-Frequency and Low-Amplitude Vibrations