Simulation of liquid imidazole using a high-rank quantum topological electrostatic potential
Majeed S Shaik1, Steven Y Liem, Yongna Yuan
1Manchester Interdisciplinary Biocentre (MIB), 131 Princess Street, Univ. of Manchester, Manchester M1 7DN, UK.
Physical Chemistry Chemical Physics : PCCP
|October 23, 2010
Summary
Multipolar electrostatics in liquid imidazole simulations reveal distinct molecular arrangements compared to point charge models. This finding impacts understanding of imidazole
Area of Science:
- Computational chemistry
- Materials science
- Biochemistry
Background:
- Imidazole is crucial in life and materials science due to its lone pair and π system.
- These features suggest significant contributions from multipolar electrostatic interactions.
Purpose of the Study:
- To investigate the influence of multipolar electrostatics on liquid imidazole's structure, dynamics, and thermodynamics.
- To compare these effects against traditional atomic point charge models.
Main Methods:
- Rigid body molecular dynamics simulations were performed on pure liquid imidazole at various temperatures (1 atm).
- Atomic multipole moments derived from ab initio electron densities modeled electrostatic interactions.
- Lennard-Jones parameters were fitted to experimental liquid density for non-electrostatic terms.
Main Results:
- Multipolar electrostatics accurately represent liquid imidazole, unlike point charge models.
- Point charge models overestimate π-stacked dimers and underestimate hydrogen-bonded dimers.
- Temperature effects on liquid imidazole's local structure were analyzed via radial and spatial distribution functions.
Conclusions:
- Multipolar electrostatics provide a more accurate description of liquid imidazole's local structure and interactions.
- The choice of electrostatic model significantly impacts the predicted molecular arrangements in liquid imidazole.
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