Detecting vapour bubbles in simulations of metastable water

Autor(en)

Miguel A. Gonzalez, Georg Menzl, Juan L. Aragones, Philipp Geiger, Frederic Caupin, Jose L. F. Abascal, Christoph Dellago, Chantal Valeriani

Abstrakt

The investigation of cavitation in metastable liquids with molecular simulations requires an appropriate definition of the volume of the vapour bubble forming within the metastable liquid phase. Commonly used approaches for bubble detection exhibit two significant flaws: first, when applied to water they often identify the voids within the hydrogen bond network as bubbles thus masking the signature of emerging bubbles and, second, they lack thermodynamic consistency. Here, we present two grid-based methods, the M-method and the V-method, to detect bubbles in metastable water specifically designed to address these shortcomings. The M-method incorporates information about neighbouring grid cells to distinguish between liquid- and vapour-like cells, which allows for a very sensitive detection of small bubbles and high spatial resolution of the detected bubbles. The V-method is calibrated such that its estimates for the bubble volume correspond to the average change in system volume and are thus thermodynamically consistent. Both methods are computationally inexpensive such that they can be used in molecular dynamics and Monte Carlo simulations of cavitation. We illustrate them by computing the free energy barrier and the size of the critical bubble for cavitation in water at negative pressure.

Organisation(en)

Computergestützte Physik und Physik der Weichen Materie

Externe Organisation(en)

Universidad Complutense De Madrid, Massachusetts Institute of Technology, Université Claude-Bernard-Lyon-I

Journal

Journal of Chemical Physics

Band

141

Anzahl der Seiten

13

ISSN

0021-9606

DOI

https://doi.org/10.1063/1.4896216

Publikationsdatum

11-2014

Peer-reviewed

Ja

ÖFOS 2012

103036 Theoretische Physik, 103029 Statistische Physik

Schlagwörter

ASJC Scopus Sachgebiete

Allgemeine Physik und Astronomie, Physical and Theoretical Chemistry

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/b3b5db4f-9426-4484-a40c-3a4b39b30728