## 3 Results and Discussion
There was no such component observed, as shown on some selected spectra in Figure 8.  
In contrast to the case of FeIII(2)-containing samples, the temperature variation of the spectral area for both components showed regular behavior. The statistical uncertainty for the ferrate(VI) is attributed to the low resolution resulting in small spectral areas. (It is considered accidental that the smaller FeIII(1) does not show this statistical variance.) In order to confirm the regular behavior of FeIII(1), another sample was selected for detailed study where only FeIII(1) was present as a degradation product but in a larger quantity (Experiment 8). A velocity span of \(\pm 6\) mm/s was set for better resolution while guaranteeing to see magnetic sextets if there were any (Figure 9). It is obvious that the spectra are free from any magnetic components. They constitute only the subspectra of the ferrate(VI) and its single degradation product FeIII(1). The evaluated Mossbauer parameters are shown in Table 3.  
Plotting the normalized spectral areas as a function of temperature, both components showed regular behavior (Figure 9). This was the first situation where calculating the Debye temperatures for the two spectral components ferrate(VI) and the iron(III) degradation product (FeIII(1)) was feasible. The Debye fits are shown in Figure 10.  
It is found that the difference in the Debye temperatures is not significant. Unfortunately, the calculated errors are high, which is due to the low spectral areas relative to the baseline. The respective Mossbauer-Lamb factors can be calculated from the Debye temperatures as shown in Table 4.  
Figure 8: Selected Mössbauer spectra of a ferrate(VI) sample containing FeIII(1) as an iron(III) degradation product, recorded in wide velocity range at the indicated temperatures (Experiment 6), together with the temperature variation of the normalized areas for ferrate(VI) (purple squares) and FeIII(1) (orange dots). It has to be mentioned that, as could be seen in the various experiments, the normalized spectrum area for the ferrate(VI) component was mostly regular, showing a more or less monotonous decrease with the temperature. Performing the Debye calculations for six more cases, the average Debye temperature for the ferrate(VI) was obtained as \(\Theta_{\text{D}}=252(14)\) K, \begin{table}
\begin{tabular}{c c c c c} \hline \hline  & \multicolumn{2}{c}{**Ferrate(VI)**} & \multicolumn{2}{c}{**Fe\({}^{\text{III}}\)(1)**} \\ \hline \(\boldsymbol{T\) [K]} & \(\boldsymbol{\delta\) (mm/s)} & \(\boldsymbol{\Delta\) (mm/s)} & \(\boldsymbol{\delta\) (mm/s)} & \(\boldsymbol{\Delta\) (mm/s)} \\ \hline
**87.5** & \(-0.838\) & \(0.13\) & \(0.468\) & \(0.257\) \\ \hline
**110** & \(-0.852\) & \(0.11\) & \(0.46\) & \(0.26\) \\ \hline
**130** & \(-0.855\) & \(0.113\) & \(0.454\) & \(0.261\) \\ \hline
**150** & \(-0.861\) & \(0.111\) & \(0.447\) & \(0.259\) \\ \hline
**170** & \(-0.865\) & \(0.129\) & \(0.434\) & \(0.267\) \\ \hline
**190** & \(-0.866\) & \(0.108\) & \(0.426\) & \(0.262\) \\ \hline
**210** & \(-0.886\) & \(0.134\) & \(0.42\) & \(0.245\) \\ \hline
**230** & \(-0.885\) & \(0.115\) & \(0.4\) & \(0.263\) \\ \hline
**250** & \(-0.898\) & \(0.11\) & \(0.397\) & \(0.265\) \\ \hline \end{tabular}
\end{table} 
Table 3: Mössbauer parameters found, in Experiment 8, for the ferrate(VI) and Fe\({}^{\text{III}}\)(1) species as a function of temperature. Isomer shifts are given relative to \(\alpha\)-Fe at room temperature. Errors are \(\pm 1\) in the last digit. Figure 9: Mössbauer spectra of a ferrate(VI) sample containing only Fe\({}^{\text{III}}\)(1) as a degradation product, recorded at the indicated temperatures (Experiment 8) together with the temperature variation of the normalized areas for ferrate(VI) (purple squares) and Fe\({}^{\text{III}}\)(1) (orange dots).