Langmuir Films of Anthracene Derivatives on Liquid Mercury II: Asymmetric Molecules
Abstract
The structure and phase sequence of liquid-mercury-supported Langmuir films (LFs) of anthrone and anthralin were studied by surface tensiometry and surface-specific synchrotron X-ray diffraction. In the low-coverage phase the molecules are both side-lying, rather than the flat-lying orientation found for anthracene and anthraquinone. In the high-coverage phase, the molecules are either standing up (anthrone) or remain side-lying (anthralin) on the mercury surface. In contrast with the symmetric anthracene and anthraquinone, both high-coverage phases exhibit long-range in-plane order. The order is different for the two compounds. The structural details, the role of molecular symmetry, the oxygen side groups, and the asymmetry-induced dipole moments are discussed.
- Authors:
- Publication Date:
- Research Org.:
- Brookhaven National Laboratory (BNL) National Synchrotron Light Source
- Sponsoring Org.:
- Doe - Office Of Science
- OSTI Identifier:
- 930283
- Report Number(s):
- BNL-80987-2008-JA
TRN: US0806724
- DOE Contract Number:
- DE-AC02-98CH10886
- Resource Type:
- Journal Article
- Resource Relation:
- Journal Name: Journal of Physical Chemistry C; Journal Volume: 111
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 43 PARTICLE ACCELERATORS; ANTHRACENE; DIPOLE MOMENTS; EXHIBITS; FILMS; LIQUIDS; MERCURY; MOLECULES; ORIENTATION; OXYGEN; SURFACES; SYMMETRY; SYNCHROTRONS; X-RAY DIFFRACTION; national synchrotron light source
Citation Formats
Tamam,L., Kraack, H., Sloutskin, E., Ocko, B., Pershan, P., Ofer, E., and Deutsch, M.. Langmuir Films of Anthracene Derivatives on Liquid Mercury II: Asymmetric Molecules. United States: N. p., 2007.
Web. doi:10.1021/jp063937g.
Tamam,L., Kraack, H., Sloutskin, E., Ocko, B., Pershan, P., Ofer, E., & Deutsch, M.. Langmuir Films of Anthracene Derivatives on Liquid Mercury II: Asymmetric Molecules. United States. doi:10.1021/jp063937g.
Tamam,L., Kraack, H., Sloutskin, E., Ocko, B., Pershan, P., Ofer, E., and Deutsch, M.. Mon .
"Langmuir Films of Anthracene Derivatives on Liquid Mercury II: Asymmetric Molecules". United States.
doi:10.1021/jp063937g.
@article{osti_930283,
title = {Langmuir Films of Anthracene Derivatives on Liquid Mercury II: Asymmetric Molecules},
author = {Tamam,L. and Kraack, H. and Sloutskin, E. and Ocko, B. and Pershan, P. and Ofer, E. and Deutsch, M.},
abstractNote = {The structure and phase sequence of liquid-mercury-supported Langmuir films (LFs) of anthrone and anthralin were studied by surface tensiometry and surface-specific synchrotron X-ray diffraction. In the low-coverage phase the molecules are both side-lying, rather than the flat-lying orientation found for anthracene and anthraquinone. In the high-coverage phase, the molecules are either standing up (anthrone) or remain side-lying (anthralin) on the mercury surface. In contrast with the symmetric anthracene and anthraquinone, both high-coverage phases exhibit long-range in-plane order. The order is different for the two compounds. The structural details, the role of molecular symmetry, the oxygen side groups, and the asymmetry-induced dipole moments are discussed.},
doi = {10.1021/jp063937g},
journal = {Journal of Physical Chemistry C},
number = ,
volume = 111,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
-
The structure and phase sequence of liquid-mercury-supported Langmuir films (LFs) of two symmetric acenes, anthracene and anthraquinone, were studied by surface tensiometry and X-ray diffraction. At low coverage, both form a monolayer of surface-parallel, flat-lying, molecules. At high coverage, we find a monolayer of side-lying molecules, where the molecular plane is surface-normal, and the molecular long axis is surface-parallel. None of these phases exhibit long-range in-plane order.
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