The number of boron atoms belonging to reacted units was reduced in the lower-temperature range due to a decrease in the activity of chemical reactions. The number of boron atoms undergoing reaction events is 0.25-0.50 in the glass melts at 2000 K. It can therefore be said that the number of reaction events per step is sufficiently small, meaning that the temporal resolution is sufficient to capture all chemical reactions occurring during the cooling process. The numbers of boron atoms undergoing unit transitions resulting from reaction events between AIMD steps can be represented as a reaction matrix. The reaction matrices for the a-La30, a-La50, a-La60, and a-Y50 glasses are shown in Figs. . The reaction events from A to B are represented as rows and columns corresponding to the structural units, where A and B each represent any structural unit in Fig. . The number of A → B transitions, N A→B , is normalized by the total number of transitions from A to any unit, N A→∀ :