Figure 4.

Schematic representation of the trial move attempting to perform the reaction for whole molecules for serial Rx/CFC. In this trial move, the value of λ and all positions of all molecules remain the same. We consider the reaction A ⇌ B in which A = green and B = black. The dashed spheres represent fractional molecules. The fractional molecule of A is transformed into a whole molecule of A, while at the same time a randomly selected whole molecule of B is transformed into a fractional molecule of B.