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Energy dispersive X-ray absorption spectroscopy (ED-XAS), in which the whole XAS spectrum is acquired simultaneously, has been applied to reduce the real-time for acquisition of spectra of photoinduced excited states by using a germanium microstrip detector gated around one X-ray bunch of the ESRF (100 ps). Cu K-edge XAS was used to investigate the MLCT states of [Cu(dmp)2](+) (dmp =2,9-dimethyl-1,10-phenanthroline) and [Cu(dbtmp)2](+) (dbtmp =2,9-di-n-butyl-3,4,7,8-tetramethyl-1,10-phenanthroline) with the excited states created by excitation at 450 nm (10 Hz). The decay of the longer lived complex with bulky ligands, was monitored for up to 100 ns. DFT calculations of the longer lived MLCT excited state of [Cu(dbp)2](+) (dbp =2,9-di-n-butyl-1,10-phenanthroline) with the bulkier diimine ligands, indicated that the excited state behaves as a Jahn-Teller distorted Cu(II) site, with the interligand dihedral angle changing from 83 to 60° as the tetrahedral coordination geometry flattens and a reduction in the Cu-N distance of 0.03 Å.

This study explores the influences of steric hindrance and excited state solvent ligation on the excited state dynamics of Cu(I) diimine complexes. Ultrafast excited state dynamics of Cu(I)bis(3,8-di(ethynyltrityl)-1,10-phenanthroline) [Cu(I)(detp)(2)](+) are measured using femtosecond transient absorption spectroscopy. The steady state electronic absorption spectra and measured lifetimes are compared to those of Cu(I)bis(1,10-phenanthroline), [Cu(I)(phen)(2)](+), and Cu(I)bis(2-9-dimethyl-1,10-phenanthroline), [Cu(I)(dmp)(2)](+), model complexes to determine the influence of different substitution patterns of the phenanthroline ligand on the structural dynamics associated with the metal to ligand charge transfer excited states. Similarities between the [Cu(I)(detp)(2)](+) and [Cu(I)(phen)(2)](+) excited state lifetimes were observed in both coordinating and noncoordinating solvents and attributed to the lack of steric hindrance from substitution at the 2- and 9-positions. The solution-phase X-ray absorption spectra of [Cu(I)(detp)(2)](+), [Cu(I)(phen)(2)](+), and [Cu(I)(dmp)(2)](+) are reported along with finite difference method calculations that are used to determine the degree of ground state dihedral angle distortion in solution and to account for the pre-edge features observed in the XANES region.

Valence-to-core X-ray emission spectroscopy was applied to study a composition of chromium coatings electrodeposited from Cr(III) sulfate electrolytes with the addition of formic or oxalic acid. It was shown that the obtained crystallographically amorphous deposits contain chromium carbide compounds. These results indicate that nanodimensional Cr crystallites formed during the electrodeposition process are characterized by very high electrocatalytic activity.