Application of phenomenological freezing and melting indicators to the exp-6 and Gaussian core potentials

Abstract

We apply two simple analytical melting and freezing indicators proposed earlier to the two exemplary systems exhibiting anomalous melting behaviour, exp-6 and Gaussian core models. It is shown that the main anomalous feature – re-entrant melting regime – is well reproduced. Detailed comparison with the available data from numerical simulations demonstrates, however, that the agreement is merely qualitative. This implies that in general these indicators should be used with some care for purposes other than rough estimates of the location of the fluid–solid phase change.

Keywords:

• melting and freezing
• re-entrant melting
• melting indicator
• exp-6 potential
• Gaussian core model

Acknowledgements

This work was partly supported by DLR under Grant 50WP0203. (Gefördert von der Raumfahrt-Agentur des Deutschen Zentrums für Luft und Raumfahrt e. V. mit Mitteln des Bundesministeriums für Wirtschaft und Technologie aufgrund eines Beschlusses des Deutschen Bundestages unter dem Förderkennzeichen 50 WP 0203.)