The method of expanding the wavefunction of diatomic molecules in a series of orbital angular momentum eigenfunctions (partial waves) is extended to two-electron homonuclear molecules. The angular momentum is a function of the Euler angles only; a symmetric choice of these angles is used which greatly facilitates the description of the exchange character of the wavefunction. As a result, explicit equations for the three-dimensional ``radial'' functions can be derived for all the different magnetic, parity, and exchange states. For Σ states the partial wave sums only go over alternate values of the angular momentum giving rise to the expectation of an even more rapidly convergent series in these cases.