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Experimental and four-component relativistic DFT studies of tungsten carbonyl complexes
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-07-24)
We present a theoretical and experimental study of the structure and nuclear magnetic resonance (NMR) parameters of the pentacarbonyltungsten complexes of η<sup>1</sup>-2-(trimethylstannyl)-4,5-dimethylphosphinine, η<sup>2</sup>-norbornene, and imidazolidine-2-thione. The three complexes have a pseudo-octahedral molecular structure with the six ligands bonded to the tungsten atom. The η<sup>1</sup ...
Absolute NMR shielding scales and nuclear spin–rotation constants in 175LuX and 197AuX (X= 19F, 35Cl, 79Br and 127I)
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-10-28)
We present nuclear spin–rotation constants, absolute nuclear magnetic resonance (NMR) shielding
constants, and shielding spans of all the nuclei in 175LuX and 197AuX (X =
19F, 35Cl, 79Br, 127I), calculated
using coupled-cluster singles-and-doubles with a perturbative triples (CCSD(T)) correction
theory, four-component relativistic density functional theory (relativistic DFT), and non-relativistic
DFT. ...
Excitation Energies from Real-Time Propagation of the Four-Component Dirac–Kohn–Sham Equation
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-01-21)
We report the first implementation of real-time time-dependent density functional theory (RT-TDDFT) at the relativistic four-component level of theory. In contrast to the perturbative linear-response TDDFT approach (LR-TDDFT), the RT-TDDFT approach performs an explicit time propagation of the Dirac–Kohn–Sham density matrix, offering the possibility to simulate molecular spectroscopies involving ...
Structure, solvent, and relativistic effects on the NMR chemical shifts in square-planar transition-metal complexes: Assessment of DFT approaches
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-08-25)
The role of various factors (structure, solvent, and relativistic treatment) was evaluated for square-planar 4d and 5d transition-metal complexes. The DFT method for calculating the structures was calibrated using a cluster approach and compared to X-ray geometries, with the PBE0 functional (def2-TZVPP basis set) providing the best results, followed closely by the hybrid TPSSH and the MN12SX ...
Four-Component Relativistic Density-Functional Theory Calculations of Nuclear Spin-Rotation Constants: Relativistic Effects in p-Block Hydrides
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-07-01)
We present an implementation of the nuclear spin–rotation (SR) constants based on the relativistic four-component Dirac–Coulomb Hamiltonian. This formalism has been implemented in the framework of the Hartree–Fock and Kohn–Sham theory, allowing assessment of both pure and hybrid exchange–correlation functionals. In the density-functional theory (DFT) implementation of the response equations, a ...
Four-Component Relativistic Density Functional Theory Calculations of EPR g- and Hyperfine-Coupling Tensors Using Hybrid Functionals: Validation on Transition-Metal Complexes with Large Tensor Anisotropies and Higher-Order Spin-Orbit Effects
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-12-04)
The four-component matrix Dirac-Kohn-Sham (mDKS) implementation of EPR
g- and hyperfine A-tensor calculations within a restricted kinetic balance framework in the
ReSpect code has been extended to hybrid functionals. The methodology is validated for an
extended set of small 4d1
and 5d1
[MEXn]
q
systems, and for a series of larger Ir(II) and Pt(III)
d7
complexes (S=1/2) with particularly ...
Relativistic four-component calculations of indirect nuclear spin-spin couplings with efficient evaluation of the exchange-correlation response kernel
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-03-16)
In this work, we report on the development and implementation of a new scheme for efficient
calculation of indirect nuclear spin-spin couplings in the framework of four-component matrix
Dirac-Kohn-Sham approach termed matrix Dirac-Kohn-Sham restricted magnetic balance resolution
of identity for J and K, which takes advantage of the previous restricted magnetic balance
formalism and the density ...
Linking the Character of the Metal-Ligand Bond to the Ligand NMR Shielding in Transition-Metal Complexes: NMR Contributions from Spin-Orbit Coupling
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-07-06)
Relativistic effects significantly affect various spectroscopic properties of compounds containing heavy elements. Particularly in Nuclear Magnetic Resonance (NMR) spectroscopy, the heavy atoms strongly influence the NMR shielding constants of neighboring light atoms. In this account we analyze paramagnetic contributions to NMR shielding constants and their modulation by relativistic spin–orbit ...
Indirect NMR spin-spin coupling constants in diatomic alkali halides
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-12-28)
We report the Nuclear Magnetic Resonance (NMR) spin–spin coupling constants for diatomic alkali halides MX, where M = Li, Na, K, Rb, or Cs and X = F, Cl, Br, or I. The coupling constants are determined by supplementing the non-relativistic coupled-cluster singles-and-doubles (CCSD) values with relativistic corrections evaluated at the four-component density-functional theory (DFT) level. These ...
Four-component relativistic density functional theory with the polarisable continuum model: application to EPR parameters and paramagnetic NMR shifts
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-01-01)
The description of chemical phenomena in solution is as challenging as it is im-
portant for the accurate calculation of molecular properties. Here, we present the
implementation of the polarizable continuum model (PCM) in the four-component
Dirac–Kohn–Sham density functional theory framework, o
↵
ering a cost-e
↵
ective way
to concurrently model solvent and relativistic e
↵
ects. The ...