Vibrational studies in aqueous solutions

Using portable Raman spectrometers for the identification of organic compounds at low temperatures and high altitudes: exobiological applications

“…In the low-wavenumber region, the Raman band at 521 cm −1 and the strong band at 505 cm −1 are assigned to OCO bending, and the lowest wavenumber band observed by the portable instrument at 224 cm −1 corresponds probably to T 2 (H 2 O) (Edwards & Falk 1997). All the bands observed by the portable instrument at high-altitude outdoors conditions correspond well to the values obtained using the bench instrument as well as to the data published by Shippey (1980).…”

Vibrational spectra of lead(II) oxalate

“…Therefore, we have attempted to interpret the vibrational spectra on this basis, and Table 1 shows the distribution of the fundamental vibrations of the anion under D 2h symmetry. The spectral assignments were performed on the basis of known studies on the spectroscopic behavior of the oxalate ion in aqueous solutions [22,23] as well as in the crystalline alkalinemetal oxalates [21,24,25] complemented with the information of our previous studies. [1 -3] The proposed assignment is shown in Table 2, and briefly discussed below:…”

“…[23] This allows discriminating the relative position of the ν 8 and ν 5 modes. • The assignment δ as (O-C-O) > δ s (O-C-O) was arrived at on the basis of the results of the alkaline-metal oxalate spectra.…”

The entropies of polyatomic gaseous ions

“…Further contributions arise from conflicting assignments of the other vibrations, e.g., the sets given by Jones (1980)206 or by 207 for aqueous oxalate lead to (less the v4 contribution) differing by 1.7 J K"1 mol"1 from that calculated from the data of Begun (1963). 202 The total uncertainty in Sj°(g) is estimated at ±1.8 J K"1 mol"1.…”