Method for searching for molecular stable structure, program for searching for molecular stable structure, and device for searching for molecular stable structure

Provided are a method for searching for a molecular stable structure, a program for searching for a molecular stable structure, and a device for searching for a molecular stable structure, which are capable of acquiring a stable structure and various locally stable structures from a structural formula of a compound in a short time and with high accuracy. A three-dimensional structure is generated from the structural formula of the compound, and a locally stable structure is obtained from the three-dimensional structure. A one-dimensional or multidimensional energy distribution function for one or a plurality of internal coordinates and a probability distribution function of increasing a probability of low-energy internal coordinates are calculated from internal coordinates and an energy value of the locally stable structure. The method for searching for a molecular stable structure repeats the following processes: generating a three-dimensional structure based on the calculated probability distribution function; acquiring a locally stable structure; reflecting internal coordinates and an energy value of the obtained locally stable structure on the energy distribution function and the probability distribution function; and acquiring the locally stable structure, thereby obtaining a plurality of the locally stable structures and a structure with lowest energy. The program and the device for searching for a molecular stable structure execute the method.