We investigated optical absorption spectra near the fundamental absorption edge of β-FeSi2 single crystals by transmission measurements. The phonon structure corresponding to the emission and absorption component was clearly observed in the low-temperature absorption spectra. Assuming exciton state in the indirect allowed transition, we determined a phonon energy of 0.031 ± 0.004 eV. A value of...

We report the infrared (IR) absorption spectra of different conformational isomers of gas phase amino acid molecules in the molecular fingerprint region of 330-1500 cm(-1). The IR absorption spectra for three conformers of the amino acid tryptophan show absorption bands that uniquely identify the conformational structure of the molecule and that are well matched by density functional theory cal...

This research is an attempt to measure the effect of alkyl tail on the visible spectra and order parameters S of some azo N-ester-1,8-naphthalimide(ANEN) disperse dyestuff. For the first time, the visible absorption spectra of two azo N-ester-1,8-naphthalimide(ANEN) dyes with identical molecular size and diverse alkyl tails were obtained in liquids and liquid crystalline solvent. Ordinary organ...

In the room temperature and nitrogen conditions, we presented well-resolved absorption spectra and indexes of refraction of bactericide molecules in the far infrared radiation (FIR) spectral region recorded by terahertz time-domain spectroscopy (THz-TDS). As illustrative examples we discussed the absorption spectra of captan and folpet in THz region. The absorption coefficient and index of refr...

the present work comprises the synthesis of one series of diarylmethane dyes containing one or more terminal methoxy substituents together with a variable tertiary amino group. the electronic absorption spectra of the dyes have been determined. as the conjugation of the terminal nitrogen atom improves in the sequence nmez > kairoline > julolidine, a progressive hypsochromic shift is observed

Fluorescence yield (FY) detected x-ray absorption spectra (XAS) of 3d transition metal ions are calculated from the integrated 2p3d resonant x-ray emission spectra. The resulting FY-XAS spectra are compared with the normal XAS spectra corresponding to the absorption cross section and significant deviations between the two spectra are found. This implies that the assumption that the FY-XAS spect...

in this work facile sol-gel (pechni) method has been successfully established to synthesize zn4b6o13 nanocrystals which have cubic crystals with lattice parameter: a =7.48 a. the structure and morphology of the obtained material were studied by x-ray diffraction (xrd), infrared spectra (ir), scanning electron microscopy (sem) and photoluminescence analysis. the experimental results show a band ...

Absorption and electro-absorption (Stark effect) spectra of polycrystalline and lyophillized samples of pheophorbides and bacteriopheophorbides have been measured in order to obtain information on the consequences of intermolecular interactions on electronic structure. The results support the general hypothesis that large red shifts in the absorption spectra of photosynthetic aggregates are ass...