On the centre of mass velocity in molecular dynamics simulations
Molecular dynamics simulations are performed on a fluid at supercritical conditions to analyze the effect that the velocity of centre of mass (VCOM) of the system has on temperature and phase stability. Standard rescaling velocities and Nos´e-Hoover chains of thermostats methods are used to carry ou...
| Autores: | , , , |
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| Tipo de documento: | artigo |
| Estado: | Versão publicada |
| Data de publicação: | 2012 |
| País: | México |
| Recursos: | Universidad Autónoma Metropolitana |
| Repositório: | Redalyc-UAM |
| OAI Identifier: | oai:redalyc.org:57023526008 |
| Acesso em linha: | https://www.redalyc.org/articulo.oa?id=57023526008 |
| Access Level: | Acceso aberto |
| Palavra-chave: | Física, Astronomía y Matemáticas Nosé Hoover chains Molecular dynamics scaling velocities centre of mass velocity |
| Resumo: | Molecular dynamics simulations are performed on a fluid at supercritical conditions to analyze the effect that the velocity of centre of mass (VCOM) of the system has on temperature and phase stability. Standard rescaling velocities and Nos´e-Hoover chains of thermostats methods are used to carry out simulations on SquareWell, Lennard-Jones and Soft Primitive potential models. Removing the VCOM at the beginning or during the simulation is not required for the Nos´e-Hoover chain of thermostats to keep the correct temperature of the system, however, it is fundamental to keep null the VCOM when the traditional rescaling velocity scheme is used. It is shown that if the VCOM is removed only at the beginning of the simulation the internal and external temperatures are not the same for very long simulations and the fluid becomes a solid. The temperatures and physical properties obtained using the Nos´e-Hoover chain method are the same as those obtained by removing the VCOM during the simulation in the rescaling velocity procedure. |
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