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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 ...
Anomalous phosphorescence from an organometallic white-light phosphor
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-09-25)
We report theoretical results on the possible violation of Kasha’s rule in the
phosphorescence process of (acetylacetonato)bis(1-methyl-2-phenylimidazole)iridium(III), and
show that the anomalous emission from both the T1 and T2 states is key to its white-light
phosphorescence. This analysis is supported by the calculated Boltzmann-averaged
phosphorescence lifetime of 2.21 μs, estimated including ...
Interplay of twist angle and solvents with two-photon optical channel interference in aryl-substituted BODIPY dyes
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-10-11)
Channel interference plays a crucial role in understanding the physics behind multiphoton absorption processes. In this work, we study the role of channel interference and solvent effects on the two-photon absorption in aryl-substituted boron dipyrromethene (BODIPY) dyes, a class of intramolecular charge-transfer (ICT) molecules. For this purpose, we consider fourteen dyes of this class with various ...
Origin of Dual-Peak Phosphorescence and Ultralong Lifetime of 4,6-Diethoxy-2-carbazolyl-1,3,5-triazine
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-03-02)
Recently, ultralong phosphorescence lifetime has been observed in 4,6-diethoxy-2-carbazolyl-1,3,5-triazine, and H-aggregation induced stabilization of the T1 state was suggested as its source. The response theory calculations demonstrate that the Davydov stabilization of the T1 state of the dimer is marginal with respect to the monomer and the corresponding transition moments are virtually the same. ...
Cryptophanes for Methane and Xenon Encapsulation: A Comparative Density Functional Theory Study of Binding Properties and NMR Chemical Shifts
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-11-27)
The host-guest
chemistry of
cryptophanes is an active
research area because of
its applications in sensor
design, targeting small
molecules and atoms in
environmental and
medical sciences. As such, the computational prediction of binding energies and nuclear
magnetic resonance (NMR) properties of different cryptophane complexes are of interest to
both theoreticians and experimentalists ...
Ab initio and relativistic DFT study of spin–rotation and NMR shielding constants in XF6 molecules, X = S, Se, Te, Mo, and W
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
Open-Ended Recursive Calculation of Single Residues of Response Functions for Perturbation-Dependent Basis Sets
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-09-09)
We present theory, implementation, and applications of a recursive scheme for the calculation of single residues of response functions that can treat perturbations that affect the basis set. This scheme enables the calculation of nonlinear light absorption properties to arbitrary order for other perturbations than an electric field. We apply this scheme for the first treatment of two-photon circular ...
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. ...
Shape-dependent electronic excitations in metallic chains
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
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 ...