Radiative and nonradiative transitions in the Eu(III) hexaaza macrocyclic complex (Eu(C/sub 22/H/sub 26/N/sub 6/) (CH/sub 3/COO))(CH/sub 3/COO)Cl X 2H/sub 2/O

Journal Article · Thu Aug 27 04:00:00 EDT 1987 · J. Phys. Chem.; (United States)

DOI:https://doi.org/10.1021/j100302a011· OSTI ID:6085538

Sabbatini, N; De Cola, L; Vallarino, L M; Blasse, G

The photophysical properties of the hexaaza macrocyclic complex (Eu(C/sub 22/H/sub 26/N/sub 6/)(CH/sub 3/COO)CL X 2H/sub 2/O are reported in water solution and in the solid state. The absorption spectrum and the luminescence spectrum and lifetime show that the Eu/sup 3 +/-macrocycle moiety remains unaltered in water solution, while the remaining coordination positions are occupied by the acetate anion or water molecules depending on the concentration of the complex. Luminescence decay measurements performed as a function of temperature (300 or 77 K) and solvent (H/sub 2/O or D/sub 2/O) indicate that no low-lying charge-transfer level is present and only one water molecule is coordinated to the Eu/sup 3 +/ ions in the presence of added acetate anions. The Eu/sup 3 +/ luminescence is quite efficient for f-f excitation (Phi/sub em/ approx. 0.1) while it becomes very inefficient for excitation into the ligand (Phi/sub em/ approx. 6 x 10..pi../sup 3/). The efficiency of the energy transfer from the ligand to Eu/sup 3 +/ deduced from the emission quantum yields is compared to that calculated from the luminescence of the ligand (obtained for the Gd/sup 3 +/ complex at 4.2 K) and Eu/sup 3 +/ absorption, using the Foerster-Dexter theory.

• Research Organization: Isituto Chimico G. Ciamician dell'Universita, Bologna, Italy
• OSTI ID: 6085538
• Journal Information: J. Phys. Chem.; (United States), Journal Name: J. Phys. Chem.; (United States) Vol. 91:18; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400500* -- Photochemistry
ABSORPTION SPECTRA
ABSORPTION SPECTROSCOPY
AQUEOUS SOLUTIONS
CHEMISTRY
COMPLEXES
DATA
DISPERSIONS
EFFICIENCY
EMISSION SPECTRA
EMISSION SPECTROSCOPY
ENERGY LEVELS
EUROPIUM COMPLEXES
EXCITED STATES
EXPERIMENTAL DATA
HYDROGEN COMPOUNDS
INFORMATION
LIFETIME
LUMINESCENCE
MATHEMATICAL MODELS
MIXTURES
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXYGEN COMPOUNDS
PHOTOCHEMISTRY
QUANTUM EFFICIENCY
RARE EARTH COMPLEXES
SOLIDS
SOLUTIONS
SPECTRA
SPECTROSCOPY
TEMPERATURE DEPENDENCE
WATER