Self-diffusion coefficient of bulk and confined water: a critical review of classical molecular simulation studies

ABSTRACT

We present a detailed overview of classical molecular simulation studies examining the self-diffusion coefficient of water. The self-diffusion coefficient is directly associated with the calculations of tracer or mutual diffusion coefficient of mixtures and, therefore, is a fundamental transport property, essential for an accurate description of mass transfer processes in biological, geological (i.e. energy or environmentally related), and chemical systems. In the current review we explore two distinct research areas. Namely, we discuss the self-diffusion of water in the bulk phase and under confinement. Different aspects that affect the diffusion process, including the molecular models, the system-size effects, the temperature and pressure conditions and the type of confinement are discussed. Finally, possible directions for future research are outlined.

KEYWORDS:

• Self-diffusion coefficient
• water
• molecular simulations
• review

Acknowledgments

This publication was made possible by NPRP [grants number 6-1157-2-471, 6-1547-2-632, 8-1648-2-688] from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the authors. INT acknowledges partial support of the work by the project ‘Development of Materials and Devices for Industrial, Health, Environmental and Cultural Applications’ (MIS 5002567) which is implemented under the ‘Action for the Strategic Development on the Research and Technological Sector’, funded by the Operational Program ‘Competitiveness, Entrepreneurship and Innovation’ (NSRF 2014–2020) and co-financed by Greece and the European Union (European Regional Development Fund). OM and ME acknowledge financial support from the department of Process & Energy, TU Delft. LFMF and MBMS acknowledge the financial support from CNPq (The Brazilian National Council for Scientific and Technological Development).

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Ioannis N. Tsimpanogiannis http://orcid.org/0000-0002-3466-1873

Othonas A. Moultos http://orcid.org/0000-0001-7477-9684

Luís F. M. Franco https://orcid.org/0000-0002-9334-9660

Ioannis G. Economou http://orcid.org/0000-0002-2409-6831

Additional information

Funding

This work was supported by Qatar National Research Fund [grant number NPRP 6-1157-2-471, NPRP 6-1547-2-632, NPRP 8-1648-2-688]; partial support of the work by the project ‘Development of Materials and Devices for Industrial, Health, Environmental and Cultural Applications’ (MIS 5002567) which is implemented under the ‘Action for the Strategic Development on the Research and Technological Sector’, funded by the Operational Program ‘Competitiveness, Entrepreneurship and Innovation’ (NSRF 2014–2020) and co-financed by Greece and the European Union (European Regional Development Fund). OM and ME acknowledge financial support from the Department of Process & Energy, TU Delft. LFMF and MBMS acknowledge the financial support from CNPq (The Brazilian National Council for Scientific and Technological Development).