Limited Search Characteristics of the Scaled Hypersphere Search Method: A Systematic Case Study for Isomers of BCNOS

Efficiency of the isomer exploration of BCNOS was investigated by limited search techniques using the LADD and NRUN options of the Global Reaction Route Mapping (GRRM) program. LADD specifies the number of Anharmonic Downward Distortions (ADDs), which should be preferentially traced from the largest ADD, and NRUN specifies the number of randomly generated initial structures. When the value of NRUN was fixed and the value of LADD was varied, all relatively stable structures (with respect to the most stable structure) below 300 kJ/mol were explored for LADD=1–3. When the value of LADD was fixed and the value of NRUN was varied, most of the low energy structures were obtained for NRUN=1, and the higher energy structures were complemented for larger NRUN values.