Photophysical properties of the extract of endometallofullerenes La@C2n inortho-dichlorobenzene. Picosecond laser photolysis

The kinetics of relaxation of optical anisotropy induced by polarized light in endometallofullerenes La@C_2n inortho-dichlorobenzene was studied by picosecond laser photolysis. Decay of the optical absorption signal due to the excited states of La@C_2n follows the biexponential law with two values of relaxation time:t ₁=35±3 ps andt ₂=1100±200 ps. The lifetimet or decay of the optical anisotropy is 19±5 ps and determined by the orientational diffusion of La@C_2n . The experimentally determined lifetime of optical anisotropy agrees satisfactorily with the value yielded by the theoretical model of orientational diffusion under slip boundary conditions at the interface of the La@C_2n molecule with the solvent. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya No. 10, pp. 1921–1923, October, 1999.