Structural features of monohydrated 2-(4-fluorophenyl)ethylamine: a combined spectroscopic and computational study
Afik Shachar1, Nitzan Mayorkas, Ilana Bar
1Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel. ibar@bgu.ac.il.
Physical Chemistry Chemical Physics : PCCP
|August 24, 2017
Summary
The study reveals how a water molecule stabilizes 2-(4-fluorophenyl)ethylamine (4-FPEA) through hydrogen bonding. This monohydration insight into intra- and inter-molecular interactions is key for understanding cluster stability.
Area of Science:
- Physical Chemistry
- Molecular Spectroscopy
- Computational Chemistry
Background:
- Understanding molecular interactions is crucial for various chemical and biological processes.
- Hydration significantly influences molecular conformation and stability.
- 2-(4-fluorophenyl)ethylamine (4-FPEA) is a molecule with potential pharmaceutical relevance.
Purpose of the Study:
- To investigate the structure and stability of a singly hydrated 2-(4-fluorophenyl)ethylamine (4-FPEA-H2O) cluster.
- To determine the specific binding interactions between 4-FPEA and a water molecule.
- To elucidate the role of monohydration in stabilizing the 4-FPEA molecule.
Main Methods:
- Jet-cooled ionization-loss stimulated Raman spectroscopy was employed to study the 4-FPEA photofragment.
- Density functional theory (DFT) calculations, specifically M06-2X/6-311++G(d,p), were used to model the parent cluster.
- Comparison of experimental and computed Raman spectra, along with energy calculations and advanced computational analyses (AIM, NCI), were performed.
Main Results:
- The experimental Raman spectrum was successfully matched with a computed spectrum, identifying the most stable conformer of the 4-FPEA-H2O cluster.
- The most stable structure features a water molecule hydrogen-bonded to the nitrogen lone pair of the folded, gauche conformer of 4-FPEA.
- Atoms in Molecules (AIM) and Non-Covalent Interaction (NCI) analyses confirmed the presence and nature of the hydrogen bond and other interactions.
Conclusions:
- Monohydration of 4-FPEA leads to a stable cluster structure stabilized by a specific hydrogen bond.
- The study provides valuable insights into the intra- and inter-molecular forces governing cluster formation and stability.
- This research contributes to the fundamental understanding of solvation effects on organic molecules.
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