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Heterobimetallic complexes [SmTb(piv)6(phen)2] (1), [SmTb(piv)6(bath)2]·1.75EtOH (2a·1.75EtOH), [SmTb(piv)6(bath)2]·2EtOH (2b·2EtOH), and [SmTb(piv)6(bath)2]·EtOH (2b·EtOH), where piv is (CH3)3CCO2(-), phen is 1,10-phenanthroline, and bath is 4,7-diphenyl-1,10-phenanthroline, were synthesized and studied by X-ray diffraction. It was shown that complexes 2a·1.75EtOH and 2b·2EtOH have different molecular and crystal structures. Complexes 2a·1.75EtOH, 2b·2EtOH, and 2b·EtOH differ in the structural functions of μ2-piv anions. 2a·1.75EtOH contains two μ2-piv-κ(2)O,O' anions and two μ2-piv-κ(2)O,O,O' anions, whereas 2b·2EtOH and 2b·EtOH have four μ2-piv-κ(2)O,O' anions. According to the mass spectrometry data, the dimeric molecule [SmTb(piv)6] is the major metal-containing component of gas-phase complexes 1, 2a·1.75EtOH, and 2b·2EtOH. The characteristic features of the thermal behavior of these complexes were revealed, and their magnetic and photoluminescence (PL) properties were investigated. A unique feature of desolvated complexes 2a·1.75EtOH and 2b·2EtOH is melting at high temperatures before thermal decomposition. The magnetic properties of 1 and 2a·1.75EtOH are determined mainly by the Tb(3+) ions. The optical properties of these complexes and their homodinuclear analogs were analyzed by photoluminescence, excitation, phosphorescence, and scattering spectroscopy and by lifetime measurements at 77 K and 300 K. As the temperature decreases to 77 K, the PL intensity of Tb(3+) ions in 1 and 2a·1.75EtOH substantially increases by 40 and 100 times, respectively, compared to 300 K. The PL color evidently changes from red at 300 K to bright green at 77 K. Based on these results, the mechanism of intramolecular energy transfer between the ligand levels and Sm(3+) and Tb(3+) ions under UV radiation was proposed.

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Optical properties (photoluminescence and absorption) of Eu(bta) 3 (B) n (B = H 2 O or 1,10-phenanthroline) polycrystalline powders and fluoroacrylate polymers (FAPs) impregnated with these compounds using supercritical CO 2 (SC CO 2 ) were investigated. It was established that impregnation of Eu(bta) 3 phen into the FAPs using an SC CO 2 solution was difficult to achieve. The type of B (ancillary ligand) and the polymer matrix were shown to influence the temperature quenching of photoluminescence of Eu 3+ ions in the range 25-100 o C. A comparative analysis of quantum yields (λ ex = 300 and 380 nm) and photoluminescence decay times (λ ex = 337.1 nm) for Eu(bta) 3 B n and for Eu(bta) 3 Bn-doped FAPs was performed.Introduction. The fabrication of various planar optical devices (including sensors and opto-electronic elements) based on modern polymers has recently become a priority [1]. An effective approach to controlled modification of polymer optical properties is supercritical fluid (SCF) impregnation by molecular compounds [2] including rareearth element (REE) β-diketonates [3,4]. The important physical properties of this type of compounds relate to the sensitization of REE photoluminescence (PL) in the visible wavelength range through transfer of excitation energy from the ligand π * -level into the corresponding closely lying trivalent REE 4f-levels (antenna effect) [1]. Broad absorption bands (of the order of several eV) due to intraligand π−π * -transitions located in the near-UV spectral range are characteristic of REE β-diketonates [5, 6]. The crystal structures and optical properties of complexes such as (Dy, Tm)(bta) 3 phen (bta = 4,4,4-trifluoro-1-phenylbutan-1,3-dione; phen = 1,10-phenanthroline) [7] and Eu(fod) 3 (fod = 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedione) [3] are now well studied. The ability to use Eu(bta) 3 bipy (bipy = 2,2′-bipyridyl) and Tb(bta) 3 phen as light diodes and UV dosimeters was also demonstrated [5].Fluoroacrylate polymers (FAPs) are attractive because of their broad transparent window in the near UV and visible ranges and high thermal stability [4,8]. These useful properties make them exceedingly promising materials for fabricating novel optical elements. Intense red PL appears after SCF impregnation of Eu β-diketonates in these polymer films. The excitation sources can be incoherent emitters, e.g., UV light diodes or gas-discharge lamps, which can be useful for a whole range of practical applications. Comprehensive studies of SCF processes for modifying FAPs were performed as a function of matrix composition (chemical structure of mono-and bi-functionals, their percent content) [4]. Several features of preparing films with the maximum content of Eu β-diketonates were established.Herein processes for modifying the optical properties of highly amorphous FAPs by SCF impregnation of them with Eu(bta) 3 B n compounds (B = H 2 O or phen) are investigated. The mechanisms for relaxation of excited states of the molecules are studied. Also, the roles of the ligands and ...