Location
Coulter Hall, Room 211
Start Date
19-5-2017 3:30 PM
Description
Conjugated dendrimers have been studied for their use in preparing photoreactive materials and for their light harvesting properties. One of the goals of an experimental research group at my institution is to design and prepare flat, two-dimensional dendrimers. It has been found that when twisting occurs about the single bonds of the dendrons, there is a decrease in energy transfer and therefore loss of conjugation and reduced light harvesting properties. The experimental group has been synthesizing "flat" dendrimers that they think cannot lose this conjugation due to the ethynyl units being locked in place by ether connections. These ether connections are made during an intermediate step when a monomacrocyclic dendrimer is formed. The experimental group has successfully created a monomacrocyclic dendrimer with a three carbon ether connection. The goal of this research is to determine whether a one, two, or four carbon connection would also form this ether connection without twisting of the ethynyl units. This ether connection is in the position meta to the ethynyl groups. Another goal will be to determine if one, two, three, and/or four carbon connections can be placed ortho to the ethynyl groups. It will also be determined if amine bridges would also lock the ethynyl bridges in place and form flat dendrimers. This amine connection is studied with different carbon lengths in the bridge and also in the positions both ortho and meta to the ethynyl groups. To investigate these questions, optimum structures are computed at the SCF and DFT levels of theory. The functionals employed are B3LYP, M06-2X, and ωB97XD. All calculations use correlation consistent basis sets. Finally time-dependent DFT calculations are used to investigate the UV-Vis spectra in order to determine if these various ether and amine connections will improve conjugation within the structure.
- Shelley A. Smith, Mississippi College
- Aubrey Smyly, Mississippi College
- Brooke Nash, Mississippi College
Relational Format
Conference proceeding
Recommended Citation
Smith, Shelley A., "IL8. Why Computational Chemists Should Not Be Ignored: The Effect of Ether and Amine Bridges in the Conjugation of Monomacrocyclic Dendrimers" (2017). Southeast Theoretical Chemistry Association Meeting (SETCA). 17.
https://egrove.olemiss.edu/setca/2017/schedule/17
IL8. Why Computational Chemists Should Not Be Ignored: The Effect of Ether and Amine Bridges in the Conjugation of Monomacrocyclic Dendrimers
Coulter Hall, Room 211
Conjugated dendrimers have been studied for their use in preparing photoreactive materials and for their light harvesting properties. One of the goals of an experimental research group at my institution is to design and prepare flat, two-dimensional dendrimers. It has been found that when twisting occurs about the single bonds of the dendrons, there is a decrease in energy transfer and therefore loss of conjugation and reduced light harvesting properties. The experimental group has been synthesizing "flat" dendrimers that they think cannot lose this conjugation due to the ethynyl units being locked in place by ether connections. These ether connections are made during an intermediate step when a monomacrocyclic dendrimer is formed. The experimental group has successfully created a monomacrocyclic dendrimer with a three carbon ether connection. The goal of this research is to determine whether a one, two, or four carbon connection would also form this ether connection without twisting of the ethynyl units. This ether connection is in the position meta to the ethynyl groups. Another goal will be to determine if one, two, three, and/or four carbon connections can be placed ortho to the ethynyl groups. It will also be determined if amine bridges would also lock the ethynyl bridges in place and form flat dendrimers. This amine connection is studied with different carbon lengths in the bridge and also in the positions both ortho and meta to the ethynyl groups. To investigate these questions, optimum structures are computed at the SCF and DFT levels of theory. The functionals employed are B3LYP, M06-2X, and ωB97XD. All calculations use correlation consistent basis sets. Finally time-dependent DFT calculations are used to investigate the UV-Vis spectra in order to determine if these various ether and amine connections will improve conjugation within the structure.
- Shelley A. Smith, Mississippi College
- Aubrey Smyly, Mississippi College
- Brooke Nash, Mississippi College
Comments
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