Predicting Pt-195 NMR chemical shift using new relativistic all-electron basis set

Area of Science:

• Computational Chemistry
• Nuclear Magnetic Resonance (NMR) Spectroscopy
• Inorganic Chemistry

Background:

• Accurate characterization of molecular structures is crucial in chemistry.
• Predicting NMR properties aids experimentalists, but protocols for heavy metals like Platinum-195 (Pt-195) are limited.
• Developing efficient computational tools for Pt-195 NMR is essential for advancing heavy metal research.

Purpose of the Study:

• To present novel all-electron Gaussian basis sets (NMR-DKH) for calculating Pt-195 NMR chemical shifts.
• To develop and validate empirical models for predicting Pt-195 NMR chemical shifts in Pt(II) complexes.
• To assess the accuracy of these models against experimental data and compare them with relativistic DFT calculations.

Main Methods:

• Developed new NMR-DKH basis sets using Douglas-Kroll-Hess (DKH) second-order scalar relativistic calculations.
• Created empirical models fitted to experimental Pt-195 NMR data for 183 Pt(II) complexes.
• Validated the models using a separate set of 75 Pt(II) complexes and DFT-PBEPBE calculations.

Main Results:

• The developed NMR-DKH basis sets and empirical models accurately predict Pt-195 NMR chemical shifts.
• The best model achieved a mean absolute deviation (MAD) of 150 ppm and a mean relative deviation (MRD) of 6% on the validation set.
• These results are comparable to more computationally intensive relativistic DFT calculations.

Conclusions:

• The new NMR-DKH basis sets and empirical models provide a reliable and efficient method for predicting Pt-195 NMR chemical shifts.
• These computational tools can significantly assist in the structural characterization of Platinum(II) complexes.
• The study offers a valuable advancement in the computational chemistry of heavy metal NMR properties.