PES crossings: PE curves of the entrance He^+⋅ plus CH₃CN (solid black lines) and exit He plus CH₃CN^⋅+* (dotted-dashed red lines) channels for six different geometries determined by θ values equal to 0°, 25°, 50°, 75°, 90° and 110°. The red dotted-dashed lines have been calculated assuming the removal of an electron from the inner valence orbital 5a₁ of CH₃CN, thus forming the radical cation in an electronically excited state, but that such removal does not substantially change the geometry of the ion with respect to the neutral molecule. The positions of crossings are highlighted with blue circles.