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Crystal Structure, Luminescence and Triboluminescence of the Complex [Eu(NO3)23hmpa] NO3·HQuin
B V Bukvetskii1, I V Kalinovskaya2
1Russian Academy of Sciences, Institute of Chemistry, Far-Eastern Branch, 159, Prosp. 100-letiya Vladivostoka, Vladivostok, 690022, Russia.
Abstract:
The atomic structure of crystals of the complex [Eu(NO3)23hmpa] NO3·HQuin , (hmpa - hexamethylphosphortriamide, HQuin - quinaldic acid) characterized by intensive luminescence and triboluminescence has been determined by the X-ray method. The noncentro-symmetric crystals of the compound are rhombic : a = 16.8193(3), b = 12.2877(2), c = 27.6516(5) Å, пр. гр. Pca2(1), Z = 4, ρ calc. . = 1.427 g/сm3. The crystals have a structure of the insular type which is presented by the isolated complex molecules, outer-sphere NO3- - groups, and neutral molecules of quinaldic acid. Some structural aspects of formation of the luminescent and triboluminescent properties of the compound were discussed: the role of break planes in the crystal destruction was revealed.
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