Improvement is effected for a nucleic acid-based molecular computing system that is comprised of (i) a nucleic acid structure, (ii) at least one polynucleotide displacement molecule that can bind with the nucleic acid structure under hybridizing conditions, and (iii) a clashing polynucleotide molecule that competes with the polynucleotide displacement molecule for binding the nucleic acid structure under the hybridizing conditions. The method for such improvement entails incorporating chemical modification that inhibits the binding of the clashing molecule and the nucleic acid structure or facilitating the binding of the displacement molecule and the nucleic structure.