Solid-state dimer method for calculating solid-solid phase transitions

Xiao, Penghao; Henkelman, Graeme; Sheppard, Daniel; Rogal, Jutta

doi:10.1063/1.4873437

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Solid-state dimer method for calculating solid-solid phase transitions

Xiao, Penghao·Henkelman, Graeme·Sheppard, Daniel·Rogal, Jutta

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Abstract

The dimer method is a minimum mode following algorithm for finding saddle points on a potential energy surface of atomic systems. Here, the dimer method is extended to include the cell degrees of freedom for periodic solid-state systems. Using this method, reaction pathways of solid-solid phase transitions can be determined without having to specify the final state structure or reaction mechanism. Example calculations include concerted phase transitions between CdSe polymorphs and a nucleation and growth mechanism for the A15 to BCC transition in Mo.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY BCC LATTICES CADMIUM SELENIDES DEGREES OF FREEDOM DIMERS PERIODICITY PHASE TRANSFORMATIONS POTENTIAL ENERGY REACTION KINETICS SOLIDS

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Xiao, Penghao, Henkelman, Graeme, Sheppard, Daniel, Rogal, Jutta. 2014-05-07. Solid-state dimer method for calculating solid-solid phase transitions. https://doi.org/10.1063/1.4873437

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