Document Detail

Global optimization of ionic Mg(n)F(2n) (n=1-30) clusters.
MedLine Citation:
PMID:  16392918     Owner:  NLM     Status:  MEDLINE    
The global optimization basin-hopping (BH) method has been used to locate the global minima (GM) of Mg(n)F(2n) (n=1-30) clusters using a Born-Mayer-type potential. Some of the GM were particularly difficult to find, requiring more than 1.5 x 10(4) BH steps. We have found that both the binding energy per MgF2 unit and the effective volume of the GM isomers increase almost linearly with n, and that cluster symmetry decreases with cluster size. The data derived from the BH runs reveal a growing density of local minima just above the GM as n increases. Despite this, the attraction basin around each GM is relatively large, since after all their atomic coordinates are randomly displaced by values as high as 2.0 bohrs, the perturbed structures, upon reoptimization, relax back to the GM in more than 50% of the cases (except for n=10 and 11). The relative stabilities derived from energy second differences suggest that n=8,10,13,15, and 20 are probably the magic numbers for these systems. Mass spectrum experiments would be very useful to clarify this issue.
E Francisco; A Martín Pendás; M A Blanco
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Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  The Journal of chemical physics     Volume:  123     ISSN:  0021-9606     ISO Abbreviation:  J Chem Phys     Publication Date:  2005 Dec 
Date Detail:
Created Date:  2006-01-05     Completed Date:  2007-07-27     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0375360     Medline TA:  J Chem Phys     Country:  United States    
Other Details:
Languages:  eng     Pagination:  234305     Citation Subset:  IM    
Departamento de Química Física y Analítica, Facultad de Química, Universidad de Oviedo, E-33006 Oviedo, Spain.
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MeSH Terms
Chemistry, Physical / methods*
Computer Simulation
Fluorides / chemistry
Fluorine / chemistry*
Magnesium / chemistry*
Magnesium Compounds / chemistry
Models, Chemical
Models, Statistical
Models, Theoretical
Molecular Conformation
Monte Carlo Method
Reg. No./Substance:
0/Fluorides; 0/Magnesium Compounds; 7439-95-4/Magnesium; 7782-41-4/Fluorine; 7783-40-6/magnesium fluoride

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

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