Polarization relation with line intensities

The polarized absorption spectra show both quartet bands due to A2g-> T2g, Tij, transitions split by about 1000 cm". Intensity relations for different polarization directions are consistent with selection rules for C, symmetry. The strong jR lines, representing the zero-phonon transitions into the two Kramers sublevels of Eg, exhibit polarizations as expected for the mirror-site ions. The respective origins due to T g have been identified by comparing the low-temperature emission spectrum with absorption spectra at different temperatures. The most intense sharp lines centered near 470 nm were associated with transitions into the split-levels of T2g that is the highest state with (tig) electron configuration. However, a more profound analysis due to the pronounced vibronic sideband structure has not been given so far. 

The XeFJ cation of C4 symmetry has the vibrational representation 3Raman active, but only 3oi + 3e are allowed in infrared absorption. Nine Raman lines attributable to fundamentals of XeF/ were observed, and assigned on the basis of their relative intensities, depolarization ratios, and by comparison with the spectra of related molecules (Table 4). The strong polarized lines at ca. 670 cm" and ca. 610... 

Io(k) is the intensity of a line of the primary radiation with wavenumber k and I is the length of the atom reservoir. The sinusoidal term relates to the rotation of the polarization plane and the exponential term to the atomic absorption. As both nm and An are a function of the density of the scattering atoms, lp(k) will be proportional to the square of the density of scattering atoms (N), according to ... 

The vibrational assignment is based on many experimental and theoretical criteria, such as the intensity and polarization of the Raman lines, the contours and P-R separations in gas phase IR spectra, classical concepts such as group frequencies, and comparison with the spectra of related compounds good correspondence was found for the isotopic product and sum rules. The fundamental frequencies of liquid tellurophene and its deuteriated derivatives are reported in Table VI. 

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