The 77 K emission and excitation spectra, and 298 K infrared and absorption spectra of [Cr(progly)(2,2-tri)]ClO4 [progly=prolylglycinate, 2,2-tri=N-(2-aminoethyl)-1,2-ethanediamine] have been measured.
The vibrational intervals of the electronic ground state are extracted from emission and infrared spectra.
The twelve electronic bands due to spin-allowed and spin-forbidden transitions were assigned.
Using the observed electronic transitions, a ligand field analysis was performed to determine the metaligand bonding properties for the coordinated atoms.
It is found that the carboxylate oxygen of the progly is a strong s- and p-donor while the peptide nitrogen has weak p-donor property toward chromium(III) ion.