Calculated cross sections for low energy electron collision with OH

The hydroxyl radical, OH, is an important component of many natural and technological plasmas but there is little available information on processes involving its collisions with low-energy electrons. Low energy electron collisions with OH are studied in the framework of the R-matrix method. Potential energy curves of some of the low lying target states of doublet and quartet symmetry which go to the O(P-3)+ H(S-2), O(D-1)+ H(S-2) and O(S-1)+ H(S-2) asymptotic limits are obtained for internuclear separations between 1 and 6 a(0). Scattering calculations are performed at the OH equilibrium geometry R-e = 1.8342 a(0) to yield cross sections for elastic scattering, electronic excitations from the X (2)Pi ground state to the first three excited states of A (2)Sigma(+), a (4)Sigma(-), 1 (2)Sigma(-) symmetry and for electron impact dissociation of OH. The positions and widths for negative ion resonances in the e-OH system are used to estimate the cross section for dissociative electron attachment to OH which is found to be significant at electron energies about 1.5 eV.