We report quantum mechanical calculations of the (X) over tilde <--(C) over tilde emission spectra of SO2 at the red wing of the (C) over tilde absorption band. The near equilibrium potential energy surface of the (C) over tilde B-1(2) state is deduced by fitting experimental vibrational frequencies using an exact quantum mechanical Hamiltonian. Low-lying vibrational eigenenergies on this double minimum potential agree well with experimental frequencies and the corresponding eigenstates show some interesting features. Both spectral positions and intensities of the (X) over tilde <--(C) over tilde transitions are obtained up to 16 000 cm(-1) using a Chebyshev based spectral method, which does not explicitly construct vibrational eigenfunctions in the (X) over tilde state. The emission spectra are in reasonably good agreement with experimental measurements.