Search results for "vetysidos"
showing 3 items of 3 documents
Dimers of the Higher-Energy Conformer of Formic Acid: Experimental Observation
2012
We report on the first experimental observation of formic acid dimers composed of two molecules of the higher-energy cis conformer. The cis–cis formic acid dimers are prepared in an argon matrix by selective vibrational excitation of the ground state trans conformer (deuterated form HCOOD) combined with thermal annealing of the matrix at about 30 K. Five cis–cis formic acid dimers are predicted by ab initio calculations (interaction energies from −16.9 to −27.2 kJ molˉ¹), and these structures are used for the assignment of the experimental spectra. Selective vibrational excitation of the obtained cis–cis dimers leads to the formation of several trans–cis dimers, which supports the proposed …
Isolated glyoxylic acid-water 1:1 complexes in low temperature argon matrices
2015
Abstract The 1:1 hydrogen bonded complexes between glyoxylic acid (GA) and water are studied in low temperature argon matrices. Four different complex structures were found in deposited matrices. The lowest energy conformer (T1) of GA was found to form complex, where the water molecule was attached to the opposite side of the intramolecular hydrogen bond in the molecule (T1B). Interestingly, this complex was estimated to be +8.0 kJ mol −1 higher in energy than the most stable structure (T1A), where the water is inserted into the internal hydrogen bond, and also found in solid argon but in smaller abundance. For the second-lowest energy conformer of GA (T2), the two lowest-energy complex str…
Solid state conformational behavior and interactions of a series of aromatic oligoamide foldamers
2016
The topic of this thesis is aromatic oligoamide foldamers. The literary review of the thesis discusses the general features of foldamers and their design and then focuses on the specific examples of aromatic oligoamide foldamers. The experimental part of the thesis discusses the design and preparation of a family of aromatic oligoamide foldamers that can adopt a helical conformation. The folding is directed by intramolecular hydrogen bonding and stabilized by intramolecular aromatic interactions. The focus of the thesis is the analysis of the solid state conformations of ten foldamer analogues. The analysis is based on forty different crystal structures which are determined using single cry…