The Interest in Rigid Unit Modes
The idea of rigid unit modes was developed for crystalline materials to enable an understanding of the origin of displacive phase transitions in materials such as silicates, which can be described as infinite three-dimensional networks of corner-lined SiO4 and AlO4 tetrahedra. The idea was that rigid unit modes could act as the soft modes for displacive phase transitions.
The original work in silicates showed that many of the phase transitions in silicates could be understood in terms of soft modes that are RUMs.
After the original work on displacive phase transitions, the RUM model was also applied to understanding the nature of the disordered high-temperature phases of materials such as cristobalite, the dynamics and localised structural distortions in zeolites, and negative thermal expansion.
Read more about this topic: Rigid Unit Modes
Famous quotes containing the words interest, rigid, unit and/or modes:
“The interest in life does not lie in what people do, nor even in their relations to each other, but largely in the power to communicate with a third party, antagonistic, enigmatic, yet perhaps persuadable, which one may call life in general.”
—Virginia Woolf (18821941)
“They work, and age, and put off men
By being unattractive, or too shy,
Or having morals anyhow, none give in:
Some of them go quite rigid with disgust
At anything but marriage....”
—Philip Larkin (19221986)
“During the Suffragette revolt of 1913 I ... [urged] that what was needed was not the vote, but a constitutional amendment enacting that all representative bodies shall consist of women and men in equal numbers, whether elected or nominated or coopted or registered or picked up in the street like a coroners jury. In the case of elected bodies the only way of effecting this is by the Coupled Vote. The representative unit must not be a man or a woman but a man and a woman.”
—George Bernard Shaw (18561950)
“There are two modes of transport in Los Angeles: car and ambulance. Visitors who wish to remain inconspicuous are advised to choose the latter”
—Fran Lebowitz (b. 1951)