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131.
The consequences of the twist around the double bond in propylene for the properties of its low lying excited singlet states have been investigated by the ab initio large-scale multireference configuration interaction method (MRD-CI). A substantial increase in the dipole moments of the S1 and S2 excited states was found for a large interval of the twist angel θ = 50–130°. The variation of the VB covalent VB ionic contributions to the correlated wavefunctions of these two states a function of twisting has been analyzed. The connection with the occurence of an avoided crossing of the two excited singlets near the twist angel θ = 75°, which results in no change in dipole moment directions, is pointed out. The existence of destructive or constructive interference between acceptor and donor substitution has been investigated on the example of the pyramidalization at one of the vinylic C atoms. A competition of opposing effects matrix can invert the dipole moment direction in the excited states. Preliminary investigation of the nonadiabatic coupling elements indicates that the “sudden polarization” effect willnot disappear through vibronic coupling, and that the return of excited molecules to the ground electronic state will not be immediate. 相似文献
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Analytical and Bioanalytical Chemistry - 相似文献
136.
Dr. Franck Bertorelle Dr. K. David Wegner Martina Perić Bakulić Hussein Fakhouri Clothilde Comby-Zerbino Dr. Amin Sagar Dr. Pau Bernadó Dr. Ute Resch-Genger Prof. Vlasta Bonačić-Koutecký Dr. Xavier Le Guével Dr. Rodolphe Antoine 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(39):e202200570
Atomically precise gold nanoclusters are a fascinating class of nanomaterials that exhibit molecule-like properties and have outstanding photoluminescence (PL). Their ultrasmall size, molecular chemistry, and biocompatibility make them extremely appealing for selective biomolecule labeling in investigations of biological mechanisms at the cellular and anatomical levels. In this work, we report a simple route to incorporate a preformed Au25 nanocluster into a model bovine serum albumin (BSA) protein. A new approach combining small-angle X-ray scattering and molecular modeling provides a clear localization of a single Au25 within the protein to a cysteine residue on the gold nanocluster surface. Attaching Au25 to BSA strikingly modifies the PL properties with enhancement and a redshift in the second near-infrared (NIR-II) window. This study paves the way to conrol the design of selective sensitive probes in biomolecules through a ligand-based strategy to enable the optical detection of biomolecules in a cellular environment by live imaging. 相似文献
137.
Oriol Vallcorba Sonia Latorre Xavier Alcob Carles Miravitlles Jordi Rius 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(11):o425-o427
The title compound, C21H14N4O2S, belongs to a family of molecules possessing nonlinear optical properties in solution. Its structure has been solved from laboratory X‐ray powder diffraction data using a new direct‐space structure solution method, where the atomic coordinates are directly used as parameters and the molecular geometry is described by restraints. The molecular packing is controlled by two systems of π–π interactions and one weak edge‐to‐face interaction. 相似文献
138.
In this note, we prove an existence and uniqueness result of solution for stochastic differential delay equations with hereditary
drift driven by a fractional Brownian motion with Hurst parameter H > 1/2. Then, we show that, when the delay goes to zero, the solutions to these equations converge, almost surely and in L
p
, to the solution for the equation without delay. The stochastic integral with respect to the fractional Brownian motion is
a pathwise Riemann–Stieltjes integral. 相似文献
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