We calculate the Coulomb dissociation of ^ { 9 } Li on Pb and U targets at 28.5 MeV/A beam energy within a finite range distorted wave Born approximation formalism of the breakup reactions . Invoking the principle of detailed balance , these cross sections are used to determine the excitation function and subsequently the rate of the radiative capture reaction ^ { 8 } Li ( n , \gamma ) ^ { 9 } Li at astrophysical energies . Our method is free from the uncertainties associated with the multipole strength distributions of the ^ { 9 } Li nucleus . The rate of this reaction at a temperature of 10 ^ { 9 } K is found to be about 2900 cm ^ { 3 } mole ^ { -1 } s ^ { -1 } .