# Nosé–Hoover thermostat

From Department of Theoretical and Applied Mechanics

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**Nosé–Hoover thermostat**

## Contents

## Description of the model

Nosé–Hoover thermostat is used to keep the temperature constant in the system. Equations of motion of the thermostated harmonic oscillator have the form:

where

- is the eigen frequency

- is the initial kinetic temperature of the system

- is the current kinetic temperature of the system

- is the velocity

- is the relaxation time

- - scale for

- - scale of stiffness for

## Phase-space trajectory of thermostated harmonic oscillator

The plot shows the trajectory of the thermostated harmonic oscillator in the phase-space. The equations of motion are solved numerically using leap-frog integration scheme. The followng three parameters can be changed by the user:

1) tau =

is the relaxation time2) stiff =

is the stiffness3) scale is a scale parameter for a plot

**The last slider allows to choose the number of pre-configured experiment.**

## Authorship

This stand has been developed by Nikolai Markov.

## References

- S. Nosé (1984). "A unified formulation of the constant temperature molecular-dynamics methods". J. Chem. Phys. 81 (1): 511–519.
- W.G. Hoover, (1985). "Canonical dynamics: Equilibrium phase-space distributions". Phys. Rev. A, 31 (3): 1695–1697.
- D.J. Evans, B.L. Holian (1985) The Nose–Hoover thermostat. J. Chem. Phys. 83, 4069.