Basic relationships in electronegative plasmas with more than one species of negative ion

Earlier work on electronegative plasmas containing electrons, positive ions and a single species of negative ions is extended to cover the case when there are two or more negative ion species present. It is found that the structure of such plasmas is more complex than the single ion species case, but the expressions obtained to describe the electronegativity, the extent of the plasma regions and other parameters are recognizable generalizations. Criteria are found to determine which negative ion is concentrated in the centre of the plasma. Where it was not possible to obtain analytical approximations, computational solutions have been given.