A computer performs a first step of acquiring initial structures that are atomic arrangement structures in a three-dimensional space which a composition of a material can take, a second step of calculating first energy corresponding to structurally optimized atomic arrangement structures by performing structure optimization on one or some initial structures, a third step of predicting second energy corresponding to atomic arrangement structures obtained in a case where structure optimization is performed on other initial structure(s) by using a prediction model for the other initial structure(s), a fourth step of extracting third energy indicative of a minimum value on the basis of the first energy and the second energy, and a fifth step of outputting the third energy, a first structure, which is an atomic arrangement structure corresponding to the third energy, or the third energy and the first structure.