Repozitorij Univerze v Novi Gorici

Izpis gradiva
A+ | A- | SLO | ENG

Naslov:K-edge absorption spectra of gaseous hydrides
Avtorji:Kodre, Alojz (Avtor)
Hauko, Robert (Avtor)
Padežnik Gomilšek, Jana (Avtor)
Arčon, Iztok (Avtor)
Aquilanti, Giuliana (Avtor)
Datoteke:Gradivo nima datotek. Gradivo je morda fizično dosegljivo v knjižnici fakultete, zalogo lahko preverite v COBISS-u. Povezava se odpre v novem oknu
Jezik:Angleški jezik
Vrsta gradiva:Delo ni kategorizirano (r6)
Tipologija:1.12 - Objavljeni povzetek znanstvenega prispevka na konferenci
Organizacija:UNG - Univerza v Novi Gorici
Opis:X-ray absorption spectra in the energy region of absorption edges reveal fine details of the mechanism of inner-shell photoexcitation: in particular in spectra of free atoms or simple molecules, the simplest being gaseous hydrides [1-2]. In a collection of data from consecutive and homologous elements, analyzed by a common procedure, the reaction channels can be identified with better precision and reliability than in analysis of individual spectra. Absorption spectra of the hydrides of 3p elements (PH3, H2S in HCl) were measured at the XAFS beamline of the Elettra synchrotron in Trieste: a new type of adjustable absorption cell for measurement of noxious gases at room temperature and at low photon energies was developed for the purpose. For the analysis, data from an earlier experiment on 4p hydrides (GeH4, AsH3, H2Se, HBr), and published data of 2p hydrides (CH4, NH3, H2O, HF) [3-4] as well as SiH4 and the noble gases concluding the isoelectronic series (Ne, Ar, Kr) were adopted. The spectra are compared to respective calculated spectra, obtained by atomic HF86, GRASP codes and molecular DFT (Density functional theory) ORCA code [5]. Our analysis of the pre-edge structures showed that the energies and probabilities of singleelectron transitions into the lowermost orbitals with the molecular character were strongly affected by the symmetry of the molecule, essentially in the same way in 3p and 4p homologues, but not in 2p homologues with a stronger influence of the core charge. In transitions to higher orbitals with prevailing atomic character the influence of the molecular field is negligible. The fine structure immediately above the K edge stems from the coexcitation of valence electrons. These coexcitations can be explained as a two-step process: the inner-shell photoeffect followed by the shake-up of a valence electron predominantly to a free atomic orbital. The process is markedly different from coexcitations of more tightly bound electrons [3]. The results of relative shake-up probabilities can be compared to results of emission spectroscopies, the probabilities of double excitation to bound states show a correlation with the dissociation probability of the molecule.
Ključne besede:večelektronske vzbuditve, hidridi, rentgenska absorpcijska spektroskopija
Leto izida:2018
Št. strani:1
COBISS_ID:5220091 Povezava se odpre v novem oknu
URN:URN:SI:UNG:REP:VPDPJTBZ
Število ogledov:82
Število prenosov:0
Metapodatki:XML RDF-CHPDL DC-XML DC-RDF
Področja:Gradivo ni uvrščeno v področja.
:
  
Skupna ocena:(0 glasov)
Vaša ocena:Ocenjevanje je dovoljeno samo prijavljenim uporabnikom.

Postavite miškin kazalec na naslov za izpis povzetka. Klik na naslov izpiše podrobnosti ali sproži prenos.

Gradivo je del monografije

Naslov:Book of abstracts, European Conference on X-Ray Spectrometry - EXRS-2018
Založnik:Inštitut Jožef Stefan
Prireditelj konference:Inštitut Jožef Stefan
ISBN:978-961-264-126-9
Kraj izida:Ljubljana
Leto izida:2018
Uredniki:Matjaž Kavčič

Nazaj