Growth analysis of sodium-potassium alloy clusters from 7 to 55 atoms through a genetic algorithm approach

• Published in: Journal of molecular modeling 2014-09, Vol.20 (9), p.2421-2421, Article 2421
• Main Authors: Silva, M. X., Galvão, B. R. L., Belchior, J. C.
• Format: Article
• Language: English
• Subjects: Algorithms; Alloys - chemistry; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Computer Appl. in Life Sciences; Computer Applications in Chemistry; Computer Simulation; Energy Transfer; Models, Chemical; Models, Molecular; Molecular Medicine; Molecular Structure; Original Paper; Potassium - chemistry; Sodium - chemistry; Structure-Activity Relationship; Theoretical and Computational Chemistry; Topical Collection Brazilian Symposium of Theoretical Chemistry (SBQT2013)
• ISSN: 1610-2940; 0948-5023
• DOI: 10.1007/s00894-014-2421-3

The potential energy hypersurface associated with sodium-potassium alloy clusters is explored via an enhanced genetic algorithm, where two different operators are added to the standard evolutionary procedure. Based on the recent result that the empirical Gupta many-body potential yields reasonable results for clusters with more than seven atoms, we have employed this function in the evaluation of the energies. Agglomerates from seven to the well-established 55-atom structure are studied, and their second-order energy difference and excess energies are calculated. It is found that the most stable alloys (compared to the homonuclear counterparts) are found with the proportion of sodium atoms in the range of 30 to 40%. The experimental propensity of core-shell segregation is successfully predicted by the current approach.