Results & Discussion
Mass Spectrometry
Figure 2and Figure 6 show the masses and percentages of the compounds present in the mass spectrometric graph of the suberoyl-dichloride attachment to the ferrocene molecules and the glutaryl-dichloride attachment to the ferrocene molecules, respectively. Figure 4 shows the isotopic pattern for the dodecanedioyl-dichloride attachment to ferrocene. The molecular weight of the suberoyl-dichloride attachment is 483 g/mole. Figure 2 shows that this is the most abundant compound present. The molecular weight of the glutaryl-dichloride attachment is 441 g/mole. Figure 6 shows that the most abundant compound present has the same molecular weight. To assure that the desired compound was the same compound represented by the mass spectrometric graph an isotopic graph was often taken of the compounds. Figure 4 shows the isotopic pattern of the most abundant compound present in the mass spectrometry graph of the dodecanedioyl-dichloride attachment to ferrocene. This graph was compared to the accepted isotopic pattern of the desired molecule. The two graphs matched up very well. In all mass spectrometric graphs some of the "noise" is caused by air and air-born molecules. These air-born molecules should not have affected the results of the cyclic voltammetric studies. Because the graphs showed to share the same molecular properties of the desired compounds, it was accepted that the molecules were properly synthesized and correctly prepared for electrochemical testing.
NMR Spectrometry
Figure 3, figure 5, and figure 7 show the NMR spectrometry for the reduced attachments of suberoyl-dichloride, dodecanedioyl-dichloride, and glutaryl-dichloride to the ferrocene caps, respectively. In all of the graphs the peak at 7.26 parts per million (ppm) represents the solvent, chloroform. The two peaks around 0.00 ppm and 0.07 ppm in the graphs represent TMS and grease, respectively. These three peaks should not have influenced the behavior of the cyclic voltammetric testing. The group of peaks around 4.05 ppm represents the ferrocene caps in the molecule. The integration of each peak gives a relative number of hydrogen atoms that share like properties. Due to this phenomenon, integration of the peaks, between the peaks of the ferrocene caps and the TMS, show the number of hydrogen atoms and their neighboring atoms in the acyl chain. These three graphs show that the acylating reagents were successfully attached and that the molecules were reduced. Had there been an unreduced molecule, there would have been a separated set of peaks, indicating that four hydrogen molecules share the same properties(two hydrogen atoms for each unreduced carbon atom). Because the integration of the peaks indicates that all of the hydrogen molecules in the chain share the same property, it can be assumed that the molecule was successfully reduced. Being that the molecules were assumed to have been successfully reduced, it was also assumed that the molecules were properly synthesized and correctly prepared for electrochemical testing.
Cyclic Voltammetry
The electrochemistry in figure 8 , figure
9, and figure 10 show the reduction and oxidation
potentials for the three molecules. The top wave in each graph represents the
oxidation potential, where an electron is taken from the molecule, whereas the
bottom wave represents the potential at which the electron is placed back on
the molecule. Figure 11 shows a comparison of the properties
of the three molecules relative to the other two molecules. The cyclic voltammetric
testing on the three ferrocene derivatives showed that the redox potentials
of the ferrocene caps were not sensitive to the separation distance achieved
in these compounds. The graphs of the cyclic voltammetry performed on the molecules
showed to have the same properties in all of the ferrocene derivatives. The
energy needed to remove an electron from the molecule and then place it back
on the molecule did not vary significantly from molecule to molecule. More importantly,
there was no correlation between the separation distance and the oxidation potential
of the molecules. These graphs also showed to share the same general properties
as the model insulator, ferrocene. Because these molecules showed to have the
same graphical characteristics as the model insulator, ferrocene, and not the
model conductor, differrocene, it is fair to conclude that the molecules acted
in the same general fashion, as insulators, independent from the separation
distance between the two ferrocene caps. This would indicate that the separation
distance employed by certain molecules would not influence the electrochemical
properties of the molecule. This research may help to further study the behavior
of semiconductors without having worries that the separation distance may be
playing a role. Further studies could be performed on semiconductors to provide
stronger evidence that the separation distance does not play a role, but more
importantly behavioral studies of semiconductors may be performed without having
concern for the separation distance.
Abstract |
Introduction |
Experimental Design |
Results & Discussion |
Conclusion
