Nuclear magnetic shielding of molecule in solution based on reference interaction site model self-consistent field...

Area of Science:

• Computational Chemistry
• Quantum Chemistry
• Physical Chemistry

Background:

• Calculating nuclear magnetic shielding in solutions is crucial for understanding chemical behavior.
• Existing methods like the polarizable continuum model (PCM) have limitations in accuracy for certain systems.

Purpose of the Study:

• To develop and validate a new computational method for calculating nuclear magnetic shielding in solutions.
• To improve the prediction accuracy of chemical shifts for diverse chemical species.

Main Methods:

• The study introduces the reference interaction site model self-consistent field with spatial electron density distribution (RISM-SCF-SEDD).
• This method accounts for electrostatic solute-solvent interactions by considering electron distribution for a more realistic electronic structure in solution.
• The method was applied to a water molecule in water and to 15N chemical shifts of azines.

Main Results:

• The RISM-SCF-SEDD method demonstrated accurate predictions of chemical shifts, showing good agreement with experimental and previous computational studies.
• Validation included examining the effects of solvent temperature, density, and species, with improved accuracy for polar solvents.
• The method provided more realistic results for methanol and acetone compared to the PCM.

Conclusions:

• The RISM-SCF-SEDD method offers a more quantitative and accurate approach for predicting nuclear magnetic shielding and chemical shifts in solutions.
• This advancement is particularly beneficial for systems challenging for traditional methods like PCM.
• The developed method holds promise for broader applications in computational chemistry and materials science.