Polymer Segments at the Folding Limit: Raman Scattering for the Diglyme Benchmark
Sebastian Bocklitz1, Martin A Suhm1
1Institut für Physikalische Chemie, Georg-August-Universität Göttingen, Tammannstraße 6, 37077, Göttingen, Germany.
Summary
Methyl-capped polyethers, like diglyme, prefer stretched states but can fold. Accurate modeling requires advanced quantum chemistry to capture both chain torsion and van der Waals forces.
Area of Science:
- Polymer Chemistry
- Computational Chemistry
- Spectroscopy
Background:
- Methyl-capped polyethers are flexible polar polymers.
- Longer chains can adopt folded conformations due to intrinsic preferences.
- Understanding their conformational behavior is key for materials science.
Purpose of the Study:
- To investigate the conformational preferences of diglyme in the gas phase.
- To evaluate the accuracy of quantum chemical methods in modeling polyether conformations.
- To identify challenges in simulating flexible polar polymer chains.
Main Methods:
- Gas-phase Raman cryospectroscopy was employed.
- Quantum chemical calculations were performed.
- Three-body dispersion correction and higher-order electron correlation were utilized.
Main Results:
- Diglyme predominantly exists in a stretched conformation.
- Folded conformations are energetically close to the stretched state.
- Accurate modeling necessitates advanced computational corrections.
Conclusions:
- Oligoglymes serve as challenging benchmarks for computational chemistry.
- Simulations must balance intra-chain torsion and inter-segment van der Waals interactions.
- Advanced methods are crucial for precise prediction of flexible polar polymer behavior.
