## 3 Results
### Validation and Optimization Panel  
In Table 3, all 80 pairs of \(P_{max}\) and _Rank_\(S\) are centralized on the basis of quantum calculation variants. The analysis variant is correct and, therefore, useful only when the maximum matching score is obtained for the true sequence of candidate structures, i.e., \(P_{max}\) corresponds to _Rank_\(S=1\). This situation is fulfilled only in three variants for the independent factors (formatted cells with green background in Table 3):  
Figure 3: Lists with matching scores of mass-energy profiles—the first 20 positions in descending order of \(P_{(\%)}\)—in the cases: (a) at 5 eV for _ln_ IC descriptor and \(\Delta_{f_{\text{frag}}}\) descriptor calculated by RM1 method; (b) at 5 eV for _ln_ IC descriptor and \(\Delta_{f_{\text{frag}}}\) descriptor calculated by DFT (B3 LYP/6-31G) method. The _ln_ IC descriptor from the mass spectrum at 5 eV and \(\Delta_{f}G_{frag}\) descriptor calculated using the DFT (B3 LYP/6-31G) method (_Rank S_ = 1 at \(P_{max}\) = 84.52%),
* The _ln_ IC descriptor from the mass spectrum at 5 eV and \(\Delta_{f}H_{frag}\) descriptor calculated using the RM1 method (_Rank S_ = 1 at \(P_{max}\) = 81.99%),
* The _ln_ IC descriptor from the mass spectrum at 5 eV and \(\Delta_{f}H_{ion}\) descriptor calculated using the RM1 method (_Rank S_ = 1 at \(P_{max}\) = 79.20%). The PM7 method can also give _Rank S_ = 1 (Table 3, cells with pink background), but the respective variants only happen with a small probability (\(\equiv\)55%) when compared with the maximum. Profiles calculated with this method only offer _Rank S_ = 3 for \(P_{max}\) = 83.12%. Thus, such a quantum method is not useful in a real analysis where the true structure is established only with \(P_{max}\). The table with the results of the technique's optimization and validation (Table 3) can be considered as a docking panel of the calculated mass-energy profiles with the experimental ones. The maximum docking score (84.52%) correctly indicates the five structures. The optimal conditions of independent factors that can ensure a correct structural analysis show the following:  
* There is a tendency to increase the score with decreased electronic impact energy. The best match is performed above the ionization threshold in its vicinity. * The _ln_ IC descriptors offer better results than IC. For this reason, it can be assumed that Equation (A2) is more appropriate to describe the kinetics of dissociation under these optimal conditions. * The DFT (B3 LYP/6-31G) and RM1 quantum calculation methods provide useful values in the description of energy fragmentation profiles of acetalized monosaccharide isomers. * The \(\Delta_{f}G_{frag}\) and \(\Delta_{f}H_{frag}\) descriptors provide better results than the \(\Delta_{f}H_{ion}\) and \(\Delta_{f}G_{ion}\) descriptors. \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline \multicolumn{2}{c}{**Experimental Descriptors \(\rightarrow\)**} & \multicolumn{3}{c}{**IC**} & \multicolumn{3}{c}{_In_ **IC**} \\ \hline \multirow{2}{*}{**Calculated Descriptors \(\rightarrow\)**} & \multicolumn{3}{c}{**Fragmentation Energy**} & \multicolumn{3}{c}{**Ionic Energy**} & \multicolumn{3}{c}{**Fragmentation Energy**} & \multicolumn{3}{c}{**Ionic Energy**} \\  & & **(\(\Delta\)/\(H_{frag}\) or \(\Delta\)/\(G_{frag}\))** & **(\(\Delta\)/\(H_{ion}\) or \(\Delta\)/\(G_{ion}\))** & **(\(\Delta\)/\(H_{frag}\) or \(\Delta\)/\(G_{frag}\))** & **(\(\Delta\)/\(H_{ion}\) or \(\Delta\)/\(G_{ion}\))** & **(\(\Delta\)/\(H_{ion}\) or \(\Delta\)/\(G_{ion}\))** \\ \hline
**EI** & **QC** & _Rank S_ & \(P_{max}\) & _Rank S_ & \(P_{max}\) & _Rank S_ & \(P_{max}\) & _Rank S_ & \(P_{max}\) \\ \hline  
\hline \hline \end{tabular}
\end{table} 
Table 3: The pairs of values for _Rank S_ and \(P_{max}\) were obtained at validation and optimization of the technique with mass-energy profiles applied in EI-MS for identification of the considered acetalized monosaccharide isomers. Cells with a green background indicate the variants that accurately establish the chemical structures.