Chapter 1 Relativistic Computations of NMR Parameters from First Principles: Theory and Applications

Autschbach, Jochen; Zheng, Shao Liang

doi:10.1016/s0066-4103(09)06701-5

Cited by 148 publications

(185 citation statements)

References 265 publications

Supporting

Mentioning

177

Contrasting

Unclassified

Order By: Relevance

“…A collection of calculations performed until 2008 for the proton and halide NMR shifts in HX has been compiled in Ref. 169. It is customary to test new relativistic NMR shielding implementations on the HX series and, occasionally, on rare gas atoms; many of the recent articles reporting new technical advances cited herein provide new data for the HX series.…”

Section: G Nmr Shielding Chemical Shiftsmentioning

confidence: 99%

“…178,179 For additional examples and broader coverage of the literature on relativistic NMR and EPR calculations the reader is referred to some of the available reviews. 21,169,170,[180][181][182] Another property that plays a role in EPR and other spectroscopic techniques for paramagnetic molecules (e.g., magnetocircular dichroism) is the zero-field splitting. There have been important recent advances regarding the calculation of this property; see Schmitt et al 183 and references therein.…”

Section: H Electron G-factors Zero-field Splittingmentioning

confidence: 99%

See 1 more Smart Citation

Perspective: Relativistic effects

Autschbach

2012

The Journal of Chemical Physics

279

233

View full text Add to dashboard Cite

show abstract

Section: G Nmr Shielding Chemical Shiftsmentioning

confidence: 99%

Section: H Electron G-factors Zero-field Splittingmentioning

confidence: 99%

Perspective: Relativistic effects

Autschbach

2012

The Journal of Chemical Physics

279

233

View full text Add to dashboard Cite

show abstract

“…In the last decade, powerful relativistic quantum chemistry tools were developed to obtain the nuclear magnetic shielding and spin-spin coupling tensors in a relativistic framework. [1][2][3] In fact, relativistic effects have shown to have deep influence even in qualitative aspects of NMR spectra, as shown, e.g., in the remarkable Xe spectrum discussed in Ref. 4. However, the relation between theoretical and experimental values of the NMR nuclear magnetic shielding can only be established for the relative shielding of a same nucleus in different chemical environments, i.e., the chemical shift.…”

Section: Introductionmentioning

confidence: 99%

Theoretical study of the nuclear spin-molecular rotation coupling for relativistic electrons and non-relativistic nuclei

Aucar

Gómez

Azúa

et al. 2012

The Journal of Chemical Physics

125

View full text Add to dashboard Cite

A theoretical study of the relation between the relativistic formulation of the nuclear magnetic shielding and spin-rotation tensors is presented. To this end a theoretical expression of the relativistic spin-rotation tensor is formulated, considering a molecular Hamiltonian of relativistic electrons and non-relativistic nuclei. Molecular rotation effects are introduced considering the terms of the Born-Oppenheimer decomposition, which couple the electrons and nuclei dynamics. The loss of the simple relation linking both spectral parameters in the non-relativistic formulation is further analyzed carrying out a perturbative expansion of relativistic effects by means of the linear response within the elimination of the small component approach. It is concluded that relativistic effects on the spin-rotation tensor are less important than those of the nuclear magnetic shielding tensor.

show abstract

“…They may also be based on the electronic wave function or on electron density obtained through the DFT formalism. [23][24][25] A third option is the polarization propagator that must be considered though it is not formally based on similar grounds.…”

mentioning

confidence: 99%

Relativistic and Electron-Correlation Effects on the Nuclear Magnetic Resonance Shieldings of Molecules Containing Tin and Lead Atoms

Maldonado

Aucar

2014

J. Phys. Chem. A

View full text Add to dashboard Cite

The reference values for NMR magnetic shieldings, σ ref , are of highest importance when theoretical analysis of chemical shifts are envisaged. The fact that the non relativistically valid relationship among spin-rotation constants and magnetic shieldings is not any longer valid for heavy atoms makes that the search for σ ref for such atoms needs new strategies to follow.We present here results of σ ref that were obtained applying an own simple procedure which mix accurate experimental chemical shifts (δ) and theoretical magnetic shieldings (σ). We calculated σ(Sn) and σ(Pb) in a family of heavy-halogen containing molecules.We found out that σ ref (Sn; Sn(CH 3 ) 4 ) in gas phase should be close to 3864.11 ± We studied tin and lead shieldings of the XY 4−n Z n (X = Sn, Pb; Y , Z = H, F, Cl, Br, I) and PbH 4−n I n (n = 0, 1, 2, 3, 4) family of compounds with four-component functionals as implemented in the DIRAC code. For these systems results of calculations with RelPPA-RPA are more reliable than the DFT ones. We argue on why those DFT functionals must be modified in order to obtain more accurate results of NMR magnetic shieldings within the relativistic regime: first, there is a dependence among both, electron correlation and relativistic effects that should be introduced in some way in the functionals; and second, the DIRAC code uses standard non-relativistic functionals and the functionals B3LYP and PBE0 were parameterized only with data taken from light elements. It can explain why they are not able to properly introduce relativistic effects on nuclear magnetic shieldings.We finally show that in the analysis of magnetic shieldings for the family of compounds mentioned above, one must consider the newest and so called heavy-atom effect on vicinal heavy atoms, HAVHA. Such effects are among the most important relativistic effects in these kind of compounds.

show abstract

Chapter 1 Relativistic Computations of NMR Parameters from First Principles: Theory and Applications

Cited by 148 publications

References 265 publications

Perspective: Relativistic effects

Perspective: Relativistic effects

Theoretical study of the nuclear spin-molecular rotation coupling for relativistic electrons and non-relativistic nuclei

Relativistic and Electron-Correlation Effects on the Nuclear Magnetic Resonance Shieldings of Molecules Containing Tin and Lead Atoms

Contact Info

Product

Resources

About