A method to increase a probability of interaction of one molecule with a second molecule includes applying a sequence of temporally varying perturbations by acoustic forces and/or by electromagnetic fields or any combination thereof in at least two non-aligned directions to a volume containing the molecules. The sequence of temporally varying perturbations is chosen to produce a sequence of perturbed molecular configurations for the molecule in the volume and the sequence of perturbations is selected so as to cause the increase in probability. Initially data is obtained relating to orientations of the molecules and the sequence is selected based on the data. The data can be obtained by observation or by creating a known orientation using selected fields.