Crystal structures and triboluminescent activities of samarium(III) complexes

The triboluminescence spectra and crystal structures of 1,2-dimethylpyridinium tetrakis(2-thenoyltrifluoroacetonato)samarium(III) (1) and 1,2,6-trimethylpyridinium tetrakis(2-thenoyltrifluoroacetonato)samarium(III) (2) were determined. The triboluminescent maximums are similar to those of the photoluminescence. Complex I is centrosymmetric and the triboluminescent emission may correlate with the disorder of all S atoms, all CF3 groups and the cation. The triboluminescent activity of complex 2 may correlate with its noncentrosymmetric space group. Complex I crystallizes in the monoclinic space group P2(1)/a with cell parameters a = 19.874(2) Angstrom, b = 22.922(2) Angstrom, c = 21.188(1) Angstrom, P = 108.126(6)degrees V = 9173(1) Angstrom (3); Z = 8; R = 0.0758 and R-w = 0.1315. Complex 2 crystallizes in the monoclinic space group Pn with cell parameters a = 11.2808(6) Angstrom, b = 11.0199(5) Angstrom, c = 18.4336(9) Angstrom, beta = 108.126(6)degrees; V = 2285.28(19) Angstrom (3); Z = 4; R = 0.0347 and R-w = 0.0900. All the structures were refined by full-matrix least squares methods.