The Brønsted-Evans-Polanyi Relation and the Volcano Plot for Ammonia
Synthesis over Transition Metal Catalysts.

The Brønsted-Evans-Polanyi Relation and the Volcano Plot for Ammonia Synthesis over Transition Metal Catalysts.
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by A. Logadottir, T. H. Rod, J. K. Norskov, B. Hammer, S. Dahl, and C.
J. H. Jacobsen.

Abstract
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Using density functional calculations we show that there is an
essentially linear relationship between the activation energy for N2
dissociation and the binding energy of atomic nitrogen on a range of
transition metal surfaces. This relation, known as the
Brønsted-Evans-Polanyi relation, is further shown to depend on the
structure of the active site. The consequence of the
Brønsted-Evans-Polanyi relation in terms of the kinetics of the ammonia
synthesis process under industrial conditions are discussed, and it is
shown that the relation leads to a volcano-type dependence of the
catalytic activity on the nitrogen heat of adsorption. The result show
that density functional calculations can predict the relative catalytic
activity of different transition metals.