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Title: Direction-specific van der Waals attraction between rutile TiO 2 nanocrystals

Abstract

Mutual lattice orientations dictate the types and magnitudes of forces between crystalline particles. When lattice polarizability is anisotropic, the van der Waals dispersion attraction can, in principle, contribute to this direction dependence. Here we report direct measurement of this attraction between rutile nanocrystals, as a function of their mutual orientation and surface hydration extent. At tens of nanometers of separation the attraction is weak and shows no dependence on azimuthal alignment nor surface hydration. At separations of approximately one hydration layer the attraction is strongly dependent on azimuthal alignment, and systematically decreases as intervening water density increases. Measured forces are in close agreement with predictions from Lifshitz theory, and show that dispersion forces are capable of generating a torque between particles interacting in solution and between grains in materials.

Authors:
ORCiD logo; ORCiD logo; ORCiD logo; ORCiD logo; ORCiD logo; ; ORCiD logo; ORCiD logo; ORCiD logo
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
1358505
Report Number(s):
PNNL-SA-122696
Journal ID: ISSN 0036-8075; 49383; KC0302060
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Science; Journal Volume: 356; Journal Issue: 6336
Country of Publication:
United States
Language:
English
Subject:
Environmental Molecular Sciences Laboratory

Citation Formats

Zhang, Xin, He, Yang, Sushko, Maria L., Liu, Jia, Luo, Langli, De Yoreo, James J., Mao, Scott X., Wang, Chongmin, and Rosso, Kevin M. Direction-specific van der Waals attraction between rutile TiO 2 nanocrystals. United States: N. p., 2017. Web. doi:10.1126/science.aah6902.
Zhang, Xin, He, Yang, Sushko, Maria L., Liu, Jia, Luo, Langli, De Yoreo, James J., Mao, Scott X., Wang, Chongmin, & Rosso, Kevin M. Direction-specific van der Waals attraction between rutile TiO 2 nanocrystals. United States. doi:10.1126/science.aah6902.
Zhang, Xin, He, Yang, Sushko, Maria L., Liu, Jia, Luo, Langli, De Yoreo, James J., Mao, Scott X., Wang, Chongmin, and Rosso, Kevin M. Thu . "Direction-specific van der Waals attraction between rutile TiO 2 nanocrystals". United States. doi:10.1126/science.aah6902.
@article{osti_1358505,
title = {Direction-specific van der Waals attraction between rutile TiO 2 nanocrystals},
author = {Zhang, Xin and He, Yang and Sushko, Maria L. and Liu, Jia and Luo, Langli and De Yoreo, James J. and Mao, Scott X. and Wang, Chongmin and Rosso, Kevin M.},
abstractNote = {Mutual lattice orientations dictate the types and magnitudes of forces between crystalline particles. When lattice polarizability is anisotropic, the van der Waals dispersion attraction can, in principle, contribute to this direction dependence. Here we report direct measurement of this attraction between rutile nanocrystals, as a function of their mutual orientation and surface hydration extent. At tens of nanometers of separation the attraction is weak and shows no dependence on azimuthal alignment nor surface hydration. At separations of approximately one hydration layer the attraction is strongly dependent on azimuthal alignment, and systematically decreases as intervening water density increases. Measured forces are in close agreement with predictions from Lifshitz theory, and show that dispersion forces are capable of generating a torque between particles interacting in solution and between grains in materials.},
doi = {10.1126/science.aah6902},
journal = {Science},
number = 6336,
volume = 356,
place = {United States},
year = {Thu Apr 27 00:00:00 EDT 2017},
month = {Thu Apr 27 00:00:00 EDT 2017}
}
  • We show that in anisotropic or layered superconductors impurities induce a van der Waals attraction between flux lines. This attraction together with the disorder induced repulsion may change the low-B {endash}low-T phase diagram significantly from that of the pure thermal case considered recently by G. Blatter and V. Geshkenbein [Phys.Rev.Lett.{bold 77}, 4958 (1996)]. {copyright} {ital 1997} {ital The American Physical Society}
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