The Mie scattering and absorption cross sections for spherical particles are calculated as a function of the complex index of refraction, n = n(1) - in(2). Curves of the efficiency factors for absorption, scattering, and extinction are given for n(1) = 1.01, 1.33, 1.5, and 2 and for n(2) = 10(-4), 10(-2), 10(-1), 1, and 10. The influence of the absorption on the efficiency factors is discussed. The results are compared with previously proposed simplified expressions for these factors. The variation of the scattered intensity with angle as n(2) is varied is illustrated in some typical cases. Finally the influence of n(2) on the narrow resonances which occur for large values of n(1) is discussed.