Article

Temperature effects on the static and dynamic properties of liquid water inside nanotubes.

Departament de Física i Enginyeria Nuclear, Universitat Politècnica de Catalunya, B5 Campus Nord, 08034 Barcelona, Catalonia, Spain.
Physical Review E (impact factor: 2.26). 09/2001; 64(2 Pt 1):021504. pp.021504
Source: PubMed

ABSTRACT We report a molecular dynamics simulation study of the behavior of liquid water adsorbed in carbon nanotubes under different thermodynamic conditions. A flexible simple point charged potential has been employed to model internal and intermolecular water interactions. Water-carbon forces are modeled with a Lennard-Jones-type potential. We have studied three types of tubes with effective radii ranging from 4.1 to 6.8 A and three temperatures, from 298 to 500 K for a fixed density of 1 g/cm(3). Structure of each thermodynamic state is analyzed through the characterization of the hydrogen-bond network. Time-dependent properties such as the diffusive behavior and molecular vibrational spectra are also considered. We observe the gradual destruction of the hydrogen-bond network together with faster diffusive regimes as temperature increases. A vibrational mode absent in bulk unconstrained water appears in the power spectra obtained from hydrogen velocity autocorrelation functions for all thermodynamic states. That frequency mode should be attributed to confinement effects.

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    Annual Review of Physical Chemistry 02/2008; 59:713-40. · 14.13 Impact Factor
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Keywords

behavior
 
bulk unconstrained water
 
carbon nanotubes
 
confinement effects
 
different thermodynamic conditions
 
diffusive behavior
 
diffusive regimes
 
frequency mode
 
gradual destruction
 
hydrogen velocity autocorrelation functions
 
hydrogen-bond network
 
intermolecular water interactions
 
molecular dynamics simulation study
 
molecular vibrational spectra
 
thermodynamic state
 
thermodynamic states
 
Time-dependent properties
 
Water-carbon forces
 

J Martí