Fragment-based {sup 13}C nuclear magnetic resonance chemical shift predictions in molecular crystals: An alternative to planewave methods
Abstract
We assess the quality of fragment-based ab initio isotropic {sup 13}C chemical shift predictions for a collection of 25 molecular crystals with eight different density functionals. We explore the relative performance of cluster, two-body fragment, combined cluster/fragment, and the planewave gauge-including projector augmented wave (GIPAW) models relative to experiment. When electrostatic embedding is employed to capture many-body polarization effects, the simple and computationally inexpensive two-body fragment model predicts both isotropic {sup 13}C chemical shifts and the chemical shielding tensors as well as both cluster models and the GIPAW approach. Unlike the GIPAW approach, hybrid density functionals can be used readily in a fragment model, and all four hybrid functionals tested here (PBE0, B3LYP, B3PW91, and B97-2) predict chemical shifts in noticeably better agreement with experiment than the four generalized gradient approximation (GGA) functionals considered (PBE, OPBE, BLYP, and BP86). A set of recommended linear regression parameters for mapping between calculated chemical shieldings and observed chemical shifts are provided based on these benchmark calculations. Statistical cross-validation procedures are used to demonstrate the robustness of these fits.
- Authors:
-
- Department of Chemistry, University of California, Riverside, California 92521 (United States)
- The Pennsylvania State University, The Eberly Campus, 2201 University Dr, Lemont Furnace, Pennsylvania 15456 (United States)
- Publication Date:
- OSTI Identifier:
- 22490879
- Resource Type:
- Journal Article
- Journal Name:
- Journal of Chemical Physics
- Additional Journal Information:
- Journal Volume: 143; Journal Issue: 10; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-9606
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; APPROXIMATIONS; CHEMICAL SHIFT; CLUSTER MODEL; HYBRIDIZATION; MOLECULAR CRYSTALS; NUCLEAR MAGNETIC RESONANCE; POLARIZATION; TENSORS
Citation Formats
Hartman, Joshua D., Beran, Gregory J. O.,, Monaco, Stephen, and Schatschneider, Bohdan. Fragment-based {sup 13}C nuclear magnetic resonance chemical shift predictions in molecular crystals: An alternative to planewave methods. United States: N. p., 2015.
Web. doi:10.1063/1.4922649.
Hartman, Joshua D., Beran, Gregory J. O.,, Monaco, Stephen, & Schatschneider, Bohdan. Fragment-based {sup 13}C nuclear magnetic resonance chemical shift predictions in molecular crystals: An alternative to planewave methods. United States. https://doi.org/10.1063/1.4922649
Hartman, Joshua D., Beran, Gregory J. O.,, Monaco, Stephen, and Schatschneider, Bohdan. 2015.
"Fragment-based {sup 13}C nuclear magnetic resonance chemical shift predictions in molecular crystals: An alternative to planewave methods". United States. https://doi.org/10.1063/1.4922649.
@article{osti_22490879,
title = {Fragment-based {sup 13}C nuclear magnetic resonance chemical shift predictions in molecular crystals: An alternative to planewave methods},
author = {Hartman, Joshua D. and Beran, Gregory J. O., and Monaco, Stephen and Schatschneider, Bohdan},
abstractNote = {We assess the quality of fragment-based ab initio isotropic {sup 13}C chemical shift predictions for a collection of 25 molecular crystals with eight different density functionals. We explore the relative performance of cluster, two-body fragment, combined cluster/fragment, and the planewave gauge-including projector augmented wave (GIPAW) models relative to experiment. When electrostatic embedding is employed to capture many-body polarization effects, the simple and computationally inexpensive two-body fragment model predicts both isotropic {sup 13}C chemical shifts and the chemical shielding tensors as well as both cluster models and the GIPAW approach. Unlike the GIPAW approach, hybrid density functionals can be used readily in a fragment model, and all four hybrid functionals tested here (PBE0, B3LYP, B3PW91, and B97-2) predict chemical shifts in noticeably better agreement with experiment than the four generalized gradient approximation (GGA) functionals considered (PBE, OPBE, BLYP, and BP86). A set of recommended linear regression parameters for mapping between calculated chemical shieldings and observed chemical shifts are provided based on these benchmark calculations. Statistical cross-validation procedures are used to demonstrate the robustness of these fits.},
doi = {10.1063/1.4922649},
url = {https://www.osti.gov/biblio/22490879},
journal = {Journal of Chemical Physics},
issn = {0021-9606},
number = 10,
volume = 143,
place = {United States},
year = {Mon Sep 14 00:00:00 EDT 2015},
month = {Mon Sep 14 00:00:00 EDT 2015}
}