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Title: Characterizing surface wetting and interfacial properties using enhanced sampling (SWIPES)
We introduce an accurate and efficient method for characterizing surface wetting and interfacial properties, such as the contact angle made by a liquid droplet on a solid surface, and the vapor–liquid surface tension of a fluid. The method makes use of molecular simulations in conjunction with the indirect umbrella sampling technique to systematically wet the surface and estimate the corresponding free energy. To illustrate the method, we study the wetting of a family of Lennard-Jones surfaces by water. For surfaces with a wide range of attractions for water, we estimate contact angles using our method, and compare them with contact angles obtained using droplet shapes. Notably, our method is able to capture the transition from partial to complete wetting as surface–water attractions are increased. Moreover, the method is straightforward to implement and is computationally efficient, providing accurate contact angle estimates in roughly 5 nanoseconds of simulation time.  more » « less
Award ID(s):
1652646
NSF-PAR ID:
10128345
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Soft Matter
Volume:
15
Issue:
5
ISSN:
1744-683X
Page Range / eLocation ID:
860 to 869
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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