التفاصيل البيبلوغرافية
| العنوان: |
Exact two-component theory becoming an efficient tool for NMR shieldings and shifts with spin–orbit coupling. |
| المؤلفون: |
Franzke, Yannick J.1 (AUTHOR) yannick.franzke@chemie.uni-marburg.de, Holzer, Christof2 (AUTHOR) christof.holzer@kit.edu |
| المصدر: |
Journal of Chemical Physics. 11/14/2023, Vol. 159 Issue 18, p1-19. 19p. |
| مصطلحات موضوعية: |
*SPIN-orbit interactions, *DENSITY functionals, *CHEMICAL shift (Nuclear magnetic resonance), *NUCLEAR magnetic resonance, *FINITE nuclei, *UNITARY transformations, *NUCLEAR magnetic resonance spectroscopy |
| مستخلص: |
We present a gauge-origin invariant exact two-component (X2C) approach within a modern density functional framework, supporting meta-generalized gradient approximations such as TPSS and range-separated hybrid functionals such as CAM-B3LYP. The complete exchange-correlation kernel is applied, including the direct contribution of the field-dependent basis functions and the reorthonormalization contribution from the perturbed overlap matrix. Additionally, the finite nucleus model is available for the electron-nucleus potential and the vector potential throughout. Efficiency is ensured by the diagonal local approximation to the unitary decoupling transformation in X2C as well as the (multipole-accelerated) resolution of the identity approximation for the Coulomb term (MARI-J, RI-J) and the seminumerical exchange approximation. Errors introduced by these approximations are assessed and found to be clearly negligible. The applicability of our implementation to large-scale calculations is demonstrated for a tin pincer-type system as well as low-valent tin and lead complexes. Here, the calculation of the Sn nuclear magnetic resonance shifts for the pincer-type ligand with about 2400 basis functions requires less than 1 h for hybrid density functionals. Further, the impact of spin–orbit coupling on the nucleus-independent chemical shifts and the corresponding ring currents of all-metal aromatic systems is studied. [ABSTRACT FROM AUTHOR] |
| قاعدة البيانات: |
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