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Averaged Solvent Embedding Potential Parameters for Multiscale Modeling of Molecular Properties
(Journal article; Tidsskriftartikkel, 2016-03-03)
We derive and validate averaged solvent parameters for embedding potentials to be
used in polarizable embedding quantum mechanics/molecular mechanics (QM/MM) molecular property
calculations of solutes in organic solvents. The parameters are solvent-specific atom-centered
partial charges and isotropic polarizabilities averaged over a large number of geometries of
solvent molecules. The use ...
The Elephant in the Room of Density Functional Theory Calculations
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-03-14)
Using multiwavelets, we have obtained total energies and corresponding atomization energies for the GGA-PBE and hybrid-PBE0 density functionals for a test set of 211 molecules with an unprecedented and guaranteed μHartree accuracy. These quasi-exact references allow us to quantify the accuracy of standard all-electron basis sets that are believed to be highly accurate for molecules, such as Gaussian-type ...
Energetics of saddling versus ruffling in metalloporphyrins: Unusual ruffled dodecasubstituted porphyrins
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-10-13)
Presented herein is a first major density functional theory (BP86/D3/STO-TZ2P) survey of the energetics of saddling versus ruffling for a wide range of dodecasubstituted metalloporphyrins with M = Ni, Cu, Zn, Pd, and Pt. For the majority of X<sub>8</sub>TPP (i.e., β-octasubstituted-meso-tetraphenylporphyrin), the calculations indicated a clear preference for the saddled conformation, consistent with ...
Metallo-β-lactamase inhibitors by bioisosteric replacement: preparation, activity and binding
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-14)
Bacterial resistance is compromising the use of β-lactam antibiotics including carbapenems. The
main resistance mechanism against β-lactams is hydrolysis of the β-lactam ring mediated by
serine- or metallo-β-lactamases (MBLs). Although several inhibitors of MBLs have been
reported, none has been developed into a clinically useful inhibitor. Mercaptocarboxylic acids
are among the most prominent ...
Relativistic effects on the NMR parameters of Si, Ge, Sn, and Pb alkynyl compounds: Scalar versus spin-orbit effects
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-11-01)
The NMR chemical shifts and indirect spin-spin coupling constants of 12 molecules containing <sup>29</sup>Si, <sup>73</sup>Ge, <sup>119</sup>Sn, and <sup>207</sup>Pb [X(CCMe)<sub>4</sub>, Me<sub>2</sub>X(CCMe)<sub>2</sub>, and Me<sub>3</sub>XCCH] are presented. The results are obtained from non-relativistic as well as two- and four-component relativistic density functional theory (DFT) calculations. ...
Aldol condensations on a 3-alkylidene-2,5-diketopiperazine - synthesis of two marine natural products
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-06)
The synthesis of two marine natural products containing a 3-alkylidene-6-arylidene-2,5-diketopiperazine scaffold by employing two consecutive aldol condensations starting with 1,4-diacetyl-2,5-diketopiperazine is reported. The target compounds contain a phenol or an imidazole group as aryl substituents, respectively, and suitable conditions for the aldol condensation of 1-acyl-3-alkylidene-2,5-dik ...
Differential expression profiling of ΔlitR and ΔrpoQ mutants reveals insight into QS regulation of motility, adhesion and biofilm formation in Aliivibrio salmonicida
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-03-15)
<i>Background</i>: The coordination of group behaviors in bacteria is achieved by a cell-cell signaling process called
quorum sensing (QS). QS is an intercellular communication system, which synchronously controls expression of a
vast range of genes in response to changes in cell density and is mediated by autoinducers that act as extracellular
signals. <i>Aliivibrio salmonicida</i>, the causative ...
Carbon-carbon bonds with CO2: Insights from computational studies
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-02-17)
In this mini-review, we provide an overview of recent computational studies on homogeneous transition
metal-catalyzed carbon-carbon bond formation with CO2. We cover substitution and addition reactions
involving different metals (mainly Ni, Rh, Cu) and substrates (alkanes, alkenes, alkynes, arenes) with
focus on the mechanistic details. The CO2 insertion step is generally found to be rate-limiting. ...
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. ...