Adjusting the descriptor for a crystal structure search using Bayesian optimization

We perform a crystal structure search using Bayesian optimization and evaluate its efficiency with a varying parameter value in the descriptor. Applying the crystal structure search to crystalline silicon shows that the efficiency of the search depends heavily on the parameter value. We find that the efficiency is linked to the distribution of the descriptor. Therefore, we introduce an information measure of the distribution to estimate an appropriate parameter value for performing the crystal structure search efficiently. The measure can also be used to predetermine an appropriate parameter value. The validity of the measure is confirmed with its applications to silicon oxide and yttrium-cobalt alloy.