THEORETICALLY PREDICTED LOWEST-ENERGY STRUCTURES OF WATER CLUSTERS
PILLARDY J, OLSZEWSKI KA, PIELA L
JOURNAL OF MOLECULAR STRUCTURE 270: 277-285 JUL 1992
Document type: Article |
Language: English |
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Abstract:
Optimal geometries of finite atomic or molecular clusters are difficult to
predict theoretically, because of the enormously large number of possible stable
structures. In the present paper we use our recently proposed shift method to
get the lowest-energy structures directly, without exploring the whole
configurational space. The method deforms the original potential energy
hypersurface by shifting the atom-atom components of the potential. As a result
the whole system collapses into a single point. Then, by using the so-called
reversing procedure the original potential is gradually rebuilt while the
structure is optimized in each step. The reversing procedure leads to a kind of
"big bang", because the molecules emerging from the collapse point
gradually reacquire their original internal geometry, and at the same time the
cluster geometry evolves to the final state corresponding to the original
undeformed potential. This procedure has been applied to clusters containing M =
2,3,...10 water molecules and it turned out to produce, in all cases under
study, structures of very low energy.