FRINK Linked Data Fragments server

Matches in SemOpenAlex for { <https://semopenalex.org/work/W2213698527> ?p ?o ?g. }

• W2213698527 abstract "Within this work phthalocyanine-water clusters and anthracene-argon clusters formed in superfluid helium droplets are discussed. Electronic spectroscopy on these species revealed new details about cluster formation in helium droplets and on methods for their investigation. For both species a manifold of sharp signals with line widths comparable with those of the bare chromophores’ signals could be observed in the fluorescence excitation spectra of small clusters in helium droplets. They could be assigned to clusters with distinct stoichiometries via Poisson distribution fits.Information on the stability of the clusters was provided by Stark spectra recorded for phthalocyanine-water clusters in helium droplets. They show that the van der Waals interaction between the phthalocyanine and the water molecules suffices to form clusters with a certain rigidity, whose free rotation becomes hindered in an external electric field. However, a field strength of 17 kV/cm did not suffice to accomplish an alignment of the cluster ensemble in the homogeneous electric field. A line broadening was observed for all Stark spectra of the clusters, which is interpreted as a result of the splitting and shifting of the clusters’ rotational states.The anthracene-argon clusters were investigated with excitation and dispersed emission spectroscopy. For all small clusters (less than 5 argon atoms) in helium droplets signals of isomeric one-sided and two-sided structures could be identified in the excitation spectrum. This shows that the droplet environment enables the formation and stabilization of cluster configurations, which are not observed in the gas phase. A further characteristic of high resolution helium droplet spectra is the fine structure of the excitation signals, which reveals interactions between the dopant species and its helium environment. For most anthracene-argon clusters a modification of the fine structure was observed compared with the multiplet, which is characteristic for the transitions of bare anthracene in helium droplets. This shows that the anthracene-helium interaction is altered by the argon atoms, which coagulate with the anthracene molecule. However, one anthracene-argon cluster shows excitation signals, which have an almost identical fine structure as the one observed for the bare chromophore. These signals exhibit no counterparts in the gas phase spectra and are interpreted as belonging to a cluster with the argon atom located on the anthracene-helium solvation complex instead of being directly attached to the anthracene surface.The most prominent influence on the spectral signature of the chromophores upon the addition of a small number of argon atoms or water molecules is a red shift of the transitions. This red shift of the cluster signals relative to the transitions of the bare chromophores increases with the size of the clusters. In the case of small anthracene-argon clusters this increase is basically monotonic, which is a characteristic of this species. For phthalocyanine-water the frequency regions of the signals belonging to equal-sized clusters overlap. The red shift of the cluster signals is additionally influenced by the helium droplet environment, as could be shown by comparing the helium droplet spectra of anthracene-argon with calculations of the spectral shifts for free clusters. Not only the anthracene-argon cluster configurations may differ from those in the gas phase, but also the helium solvation complexes can influence the transition frequencies. Therefore, a direct comparison of the cluster signals’ red shifts in gas phase and helium droplet spectra is not practical. In this respect it is noteworthy that the red shifts observed for the vibronic transitions of anthracene-argon clusters in helium droplets are similar to the red shifts observed for the electronic origins. Also in the case of emission spectroscopy an equal vibrational pattern was observed for bare anthracene and its argon clusters. This shows that for the regarded vibrations and within the experimental accuracy the addition of a small number of argon atoms has no material impact on the vibrational frequencies of the chromophore’s ground state and excited state.The anthracene-argon signal with the largest red shift of about 520 wavenumbers to the electronic origin of bare anthracene in helium droplets was recorded around 27100 wavenumbers. Although this signal presumably belongs to a species, where anthracene is totally embedded in the argon cluster, the broad structure of the signal and the comparison with solid argon matrix spectra indicate that the cluster size distribution still has an influence on the transitions.To conclude, the electronic spectroscopy reported in this thesis tries to contribute to the understanding of cluster formation in superfluid helium droplets." @default.
• W2213698527 created "2016-06-24" @default.
• W2213698527 creator A5011592275 @default.
• W2213698527 date "2015-12-17" @default.
• W2213698527 modified "2023-09-27" @default.
• W2213698527 title "High resolution electronic spectroscopy of van der Waals clusters formed in superfluid helium nanodroplets" @default.
• W2213698527 hasPublicationYear "2015" @default.
• W2213698527 type Work @default.
• W2213698527 sameAs 2213698527 @default.
• W2213698527 citedByCount "0" @default.
• W2213698527 crossrefType "dissertation" @default.
• W2213698527 hasAuthorship W2213698527A5011592275 @default.
• W2213698527 hasConcept C121332964 @default.
• W2213698527 hasConcept C126061179 @default.
• W2213698527 hasConcept C164866538 @default.
• W2213698527 hasConcept C178790620 @default.
• W2213698527 hasConcept C184779094 @default.
• W2213698527 hasConcept C185592680 @default.
• W2213698527 hasConcept C199360897 @default.
• W2213698527 hasConcept C32891209 @default.
• W2213698527 hasConcept C32909587 @default.
• W2213698527 hasConcept C41008148 @default.
• W2213698527 hasConcept C41999313 @default.
• W2213698527 hasConcept C49024897 @default.
• W2213698527 hasConcept C546029482 @default.
• W2213698527 hasConcept C62520636 @default.
• W2213698527 hasConceptScore W2213698527C121332964 @default.
• W2213698527 hasConceptScore W2213698527C126061179 @default.
• W2213698527 hasConceptScore W2213698527C164866538 @default.
• W2213698527 hasConceptScore W2213698527C178790620 @default.
• W2213698527 hasConceptScore W2213698527C184779094 @default.
• W2213698527 hasConceptScore W2213698527C185592680 @default.
• W2213698527 hasConceptScore W2213698527C199360897 @default.
• W2213698527 hasConceptScore W2213698527C32891209 @default.
• W2213698527 hasConceptScore W2213698527C32909587 @default.
• W2213698527 hasConceptScore W2213698527C41008148 @default.
• W2213698527 hasConceptScore W2213698527C41999313 @default.
• W2213698527 hasConceptScore W2213698527C49024897 @default.
• W2213698527 hasConceptScore W2213698527C546029482 @default.
• W2213698527 hasConceptScore W2213698527C62520636 @default.
• W2213698527 hasLocation W22136985271 @default.
• W2213698527 hasOpenAccess W2213698527 @default.
• W2213698527 hasPrimaryLocation W22136985271 @default.
• W2213698527 hasRelatedWork W1967976468 @default.
• W2213698527 hasRelatedWork W1969074327 @default.
• W2213698527 hasRelatedWork W2023201888 @default.
• W2213698527 hasRelatedWork W2040585267 @default.
• W2213698527 hasRelatedWork W2054788959 @default.
• W2213698527 hasRelatedWork W2054843186 @default.
• W2213698527 hasRelatedWork W2057094074 @default.
• W2213698527 hasRelatedWork W2062625178 @default.
• W2213698527 hasRelatedWork W2081030400 @default.
• W2213698527 hasRelatedWork W2095925896 @default.
• W2213698527 hasRelatedWork W23009265 @default.
• W2213698527 hasRelatedWork W2521893787 @default.
• W2213698527 hasRelatedWork W2807843995 @default.
• W2213698527 hasRelatedWork W2952978282 @default.
• W2213698527 hasRelatedWork W2964315139 @default.
• W2213698527 hasRelatedWork W3010839666 @default.
• W2213698527 hasRelatedWork W3157822189 @default.
• W2213698527 hasRelatedWork W3188707295 @default.
• W2213698527 hasRelatedWork W72071222 @default.
• W2213698527 hasRelatedWork W3085305682 @default.
• W2213698527 isParatext "false" @default.
• W2213698527 isRetracted "false" @default.
• W2213698527 magId "2213698527" @default.
• W2213698527 workType "dissertation" @default.