3 research outputs found
Ti<sup>3+</sup> Aqueous Solution: Hybridization and Electronic Relaxation Probed by State-Dependent Electron Spectroscopy
The electronic structure of a Ti<sup>3+</sup> aqueous solution
is studied by liquid-jet soft X-ray photoelectron (PE) spectroscopy.
Measured valence and Ti 2p core-level binding energies, together with
the Ti 2p resonant photoelectron (RPE) spectra and the derived partial
electron-yield L-edge X-ray absorption (PEY-XA) spectra, reveal mixing
between metal 3d and water orbitals. Specifically, ligand states with
metal character are identified through the enhancement of signal intensities
in the RPE spectra. An observed satellite 3d peak structure is assigned
to several different metal–ligand states. Experimental energies
and the delocalized nature of the respective orbitals are supported
by ground-state electronic structure calculations. We also show that
by choice of the detected Auger-electron-decay channel, from which
different PEY-XA spectra are obtained, the experimental sensitivity
to the interactions of the metal 3d electrons with the solvent can
be varied. The effect of such a state-dependent electronic relaxation
on the shape of the PEY-XA spectra is discussed in terms of different
degrees of electron delocalization
Probing Coster–Kronig Transitions in Aqueous Fe<sup>2+</sup> Solution Using Inverse Partial and Partial Fluorescence Yield at the L-Edge
Specific Coster–Kronig (CK) transitions in 3d
transition
metals are close to the threshold of energetic possibility, being
disallowed in free atoms, while possible in solids. Moreover, they
have been shown to be quite sensitive to chemical bonding. Nevertheless,
there has been no direct study of such behavior in solution. Here
we present an approach to quantify such transitions in solution, by
comparing relative fluorescence of different edges to their relative
absorption strengths. The difficulties of acquiring a measurement
of the absorption in solution are overcome by applying the recently
developed method of inverse partial fluorescence yield to a liquid
sample using the microjet. This method has been demonstrated on solids
to be bulk sensitive and able to obtain absorption spectra free of
self-absorption or saturation effects. We extend this approach to
investigate the L-edge of aqueous Fe<sup>2+</sup> using a combination
of a soft X-ray light source and a high-resolution X-ray emission
spectrometer
Chemical Bonding in Aqueous Ferrocyanide: Experimental and Theoretical X‑ray Spectroscopic Study
Resonant inelastic X-ray scattering
(RIXS) and X-ray absorption
(XA) experiments at the iron L- and nitrogen K-edge are combined with
high-level first-principles restricted active space self-consistent
field (RASSCF) calculations for a systematic investigation of the
nature of the chemical bond in potassium ferrocyanide in aqueous solution.
The atom- and site-specific RIXS excitations allow for direct observation
of ligand-to-metal (Fe L-edge) and metal-to-ligand (N K-edge) charge-transfer
bands and thereby evidence for strong σ-donation and π-backdonation.
The effects are identified by comparing experimental and simulated
spectra related to both the unoccupied and occupied molecular orbitals
in solution