The importance of nuclear quantum effects for NMR crystallography
arXiv:2106.14171 · doi:10.1021/acs.jpclett.1c01987
Abstract
The resolving power of solid-state nuclear magnetic resonance (NMR) crystallography depends heavily on the accuracy of computational predictions of NMR chemical shieldings of candidate structures, which are usually taken to be local minima in the potential energy. To test the limits of this approximation, we systematically study the importance of finite-temperature and quantum nuclear fluctuations for H, C, and N shieldings in polymorphs of three paradigmatic molecular crystals -- benzene, glycine, and succinic acid. The effect of quantum fluctuations is comparable to the typical errors of shielding predictions for static nuclei with respect to experiments, and their inclusion to improve the agreement with measurements, translating to more reliable assignment of the NMR spectra to the correct candidate structure. The use of integrated machine-learning models, trained on first-principles energies and shieldings, renders rigorous sampling of nuclear fluctuations affordable, setting a new standard for the calculations underlying NMR structure determinations.
References in corpus (22)
- Gaussian Approximation Potentials: the accuracy of quantum mechanics, without the electrons
- All-electron magnetic response with pseudopotentials: NMR chemical shifts
- Long-range correlation energy calculated from coupled atomic response functions
- Phase transitions of hybrid perovskites simulated by machine-learning force fields trained on-the-fly with Bayesian inference
- Nuclear quantum effects enter the mainstream
- i-PI 2.0: A Universal Force Engine for Advanced Molecular Simulations
- Ab initio thermodynamics of liquid and solid water
- Chemical Shifts in Molecular Solids by Machine Learning
- Fast and Accurate Uncertainty Estimation in Chemical Machine Learning
- Applying the Coupled-Cluster Ansatz to Solids and Surfaces in the Thermodynamic Limit
- Uncertainty estimation for molecular dynamics and sampling
- Fast and accurate quantum Monte Carlo for molecular crystals
- Anharmonic and Quantum Fluctuations in Molecular Crystals: A First-Principles Study of the Stability of Paracetamol
- A complete description of thermodynamic stabilities of molecular crystals
- A converse approach to the calculation of NMR shielding tensors
- A Bayesian approach to NMR crystal structure determination
- Lattice energies of molecular solids from the random phase approximation with singles corrections
- Temperature effects in first-principles solid state calculations of the chemical shielding tensor made simple
- Modeling the structural and thermal properties of loaded metal-organic frameworks. An interplay of quantum and anharmonic fluctuations
- Anharmonic Effects in the Low-Frequency Vibrational Modes of Aspirin and Paracetamol Crystals
- Modeling the Ga/As binary system across temperaturesand compositions from first principles
- Thermal Expansion in Dispersion-Bound Molecular Crystals