Ligand-polarization contributions to the intensity of hypersensitive trivalent lanthanide transitions

Spectroscopy Studies of Erbium and Dysprosium Acetate Single Crystals

“…For dysprosium glycinate the values of the oscillator strength for the 6H1 5/2 → 6 F11/2 "hypersensitive" transition as well as the 02 parameter are distinctly lower than for dysprosium acetate. These results are very similar to those obtained by us for holmium acetate [1] and thus confirm also the role of the dynamic-coupling mechanism in lanthanide compounds [2].…”

“…The relatively high intensity of the "hypersensitive" transition of that compound in comparison with other carboxylate complexes was explained by the dynamic coupling mechanism [2] resulting from the properties of acetate crystals, in which water molecules are bonded closer to the lanthanide ion than oxygen atoms from carboxyl groups.…”

“…It means that the polarization effect [2] caused by the more tightly bonded water molecules in the acetate structure plays an important role in the enhancement of intensity.…”

Optical Spectra of Neodymium and Europium Tungstates and Molybdates

“…In dimeric carboxylates Nd2 Ala2 (Η2 O)4 they are equal to 2. f o r 4 l 9 / 2 -4 G 5 / 2 , 2 G 7 / 2 a r e e q u a l t o 1 2 3 7 x 1 0-8 and 3885 x 10 -8 , respectively (Table I). The intensities of 4 Ι9/2 -ł 4G5/2, 2G7/2 transitions in the neodymium tungstate spectra are comparable to those observed in DMF solution of lanthanide nitrates [9], explained by polarizability mechanism of Mason [14], and are little higher than those found for lanthanide nitrate [15].…”

EuroTracker® dyes: design, synthesis, structure and photophysical properties of very bright europium complexes and their use in bioassays and cellular optical imaging

“…The spectral form of Eu emission is a sensitive function of local complex symmetry and donor atom polarisability (vide infra). 3,[16][17][18] The imposition of local C 3 symmetry, coupled with the introduction of more polarisable ligand donors (e.g. py-N > amine-N > O; carboxylate O > phosphinate O), leads to enhanced emission intensity of the electric-dipole allowed transitions around 610-620 nm ( 5 D 0 to 7 F 2 ) and to lower relative intensity in the other emission bands from the non-degenerate 5 The ease of ligand synthesis and of structural permutation is an important final aspect in probe design, (Scheme 1).…”