Figure 2. Product QM alignment parameter referenced to k′ which defines the z axis.

The alignment moment is given by the average value , where and are the rotational angular momentum operators and C is the constant that appears in equation (6). Calculations are presented for O(³P)+D₂(v=0, j=0)→OD(v′=0, j′)+D at E_coll=25 kcal mol⁻¹ on the A′ and A′′ PESs. Although the product rotational angular momentum, j′, on the A′ PES is strongly polarized perpendicular to k′ (negative values), for the A′′ PES the distribution of j′ is largely isotropic for low j′.