git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@1170 f3b2605a-c512-4ea7-a41b-209d697bcdaa

This commit is contained in:
sjplimp 2007-11-15 15:29:14 +00:00
parent 088bba6dfb
commit fb4cc15d79
8 changed files with 95 additions and 20 deletions

View File

@ -68,7 +68,9 @@ into the particle. As derived from the fluctuation/dissipation
theorum, its magnitude is proportional to sqrt(T m / dt damp), where T
is the desired temperature, m is the mass of the particle, dt is the
timestep size, and damp is the damping factor. Random numbers are
used to randomize the direction and magnitude of this force.
used to randomize the direction and magnitude of this force as
described in <A HREF = "#Dunweg">(Dunweg)</A>, where a uniform random number is used
(instead of a Gaussian random number) for speed.
</P>
<P>The desired temperature at each timestep is a ramped value during the
run from <I>Tstart</I> to <I>Tstop</I>.
@ -146,4 +148,8 @@ viscous</A>
</P>
<P><B>Default:</B> none
</P>
<A NAME = "Dunweg"></A>
<P><B>(Dunweg)</B> Dunweg and Paul, Int J of Modern Physics C, 2, 817-27 (1991).
</P>
</HTML>

View File

@ -58,7 +58,9 @@ into the particle. As derived from the fluctuation/dissipation
theorum, its magnitude is proportional to sqrt(T m / dt damp), where T
is the desired temperature, m is the mass of the particle, dt is the
timestep size, and damp is the damping factor. Random numbers are
used to randomize the direction and magnitude of this force.
used to randomize the direction and magnitude of this force as
described in "(Dunweg)"_#Dunweg, where a uniform random number is used
(instead of a Gaussian random number) for speed.
The desired temperature at each timestep is a ramped value during the
run from {Tstart} to {Tstop}.
@ -135,3 +137,6 @@ This fix is not invoked during "energy minimization"_minimize.html.
viscous"_fix_viscous.html
[Default:] none
:link(Dunweg)
[(Dunweg)] Dunweg and Paul, Int J of Modern Physics C, 2, 817-27 (1991).

View File

@ -52,10 +52,11 @@ fix 2 all nph aniso 0.0 0.0 0.0 0.0 NULL NULL 1000.0
</P>
<P>Perform constant NPH integration to update positions and velocities
each timestep for atoms in the group using a Nose/Hoover pressure
barostat. P is pressure. This creates a system trajectory consistent
with the isobaric ensemble. Unlike <A HREF = "fix_npt.html">fix npt</A>,
temperature will not be controlled if no other fix is used.
Temperature can be controlled independently by using "<A HREF = "fix_langevin.html">fix
barostat <A HREF = "#Hoover">(Hoover)</A>, implemented as described in
<A HREF = "#Melchionna">(Melchionna)</A>. P is pressure. This creates a system
trajectory consistent with the isobaric ensemble. Unlike <A HREF = "fix_npt.html">fix
npt</A>, temperature will not be controlled if no other fix
is used. Temperature can be controlled independently by using "<A HREF = "fix_langevin.html">fix
langevin</A> or <A HREF = "fix_temp_rescale.html">fix
temp/rescale</A>.
</P>
@ -197,4 +198,15 @@ pressure via Nose/Hoover.
</P>
<P>The keyword defaults are drag = 0.0 and dilate = all.
</P>
<HR>
<A NAME = "Hoover"></A>
<P><B>(Hoover)</B> Hoover, Phys Rev A, 34, 2499 (1986).
</P>
<A NAME = "Melchionna"></A>
<P><B>(Melchionna)</B> Melchionna, Ciccotti, Holian, Molecular Physics, 78,
533-44 (1993).
</P>
</HTML>

View File

@ -43,10 +43,11 @@ fix 2 all nph aniso 0.0 0.0 0.0 0.0 NULL NULL 1000.0 :pre
Perform constant NPH integration to update positions and velocities
each timestep for atoms in the group using a Nose/Hoover pressure
barostat. P is pressure. This creates a system trajectory consistent
with the isobaric ensemble. Unlike "fix npt"_fix_npt.html,
temperature will not be controlled if no other fix is used.
Temperature can be controlled independently by using ""fix
barostat "(Hoover)"_#Hoover, implemented as described in
"(Melchionna)"_#Melchionna. P is pressure. This creates a system
trajectory consistent with the isobaric ensemble. Unlike "fix
npt"_fix_npt.html, temperature will not be controlled if no other fix
is used. Temperature can be controlled independently by using ""fix
langevin"_fix_langevin.html or "fix
temp/rescale"_fix_temp_rescale.html.
@ -186,3 +187,12 @@ pressure via Nose/Hoover.
[Default:]
The keyword defaults are drag = 0.0 and dilate = all.
:line
:link(Hoover)
[(Hoover)] Hoover, Phys Rev A, 34, 2499 (1986).
:link(Melchionna)
[(Melchionna)] Melchionna, Ciccotti, Holian, Molecular Physics, 78,
533-44 (1993).

View File

@ -52,9 +52,11 @@ fix 2 water npt 300.0 300.0 100.0 aniso 0.0 0.0 0.0 0.0 NULL NULL 1000.0 dilate
</P>
<P>Perform constant NPT integration to update positions and velocities
each timestep for atoms in the group using a Nose/Hoover temperature
thermostat and Nose/Hoover pressure barostat. P is pressure; T is
temperature. This creates a system trajectory consistent with the
isothermal-isobaric ensemble.
thermostat <A HREF = "#Hoover1">(Hoover1)</A> and Nose/Hoover pressure barostat
<A HREF = "#Hoover2">(Hoover2)</A>, implemented as described in
<A HREF = "#Melchionna">(Melchionna)</A>. P is pressure; T is temperature. This
creates a system trajectory consistent with the isothermal-isobaric
ensemble.
</P>
<P>The desired temperature at each timestep is a ramped value during the
run from <I>Tstart</I> to <I>Tstop</I>. The <I>Tdamp</I> parameter is specified in
@ -201,4 +203,19 @@ the Nose/Hoover formulation.
</P>
<P>The keyword defaults are drag = 0.0 and dilate = all.
</P>
<HR>
<A NAME = "Hoover1"></A>
<P><B>(Hoover1)</B> Hoover, Phys Rev A, 31, 1695 (1985).
</P>
<A NAME = "Hoover2"></A>
<P><B>(Hoover2)</B> Hoover, Phys Rev A, 34, 2499 (1986).
</P>
<A NAME = "Melchionna"></A>
<P><B>(Melchionna)</B> Melchionna, Ciccotti, Holian, Molecular Physics, 78,
533-44 (1993).
</P>
</HTML>

View File

@ -41,9 +41,11 @@ fix 2 water npt 300.0 300.0 100.0 aniso 0.0 0.0 0.0 0.0 NULL NULL 1000.0 dilate
Perform constant NPT integration to update positions and velocities
each timestep for atoms in the group using a Nose/Hoover temperature
thermostat and Nose/Hoover pressure barostat. P is pressure; T is
temperature. This creates a system trajectory consistent with the
isothermal-isobaric ensemble.
thermostat "(Hoover1)"_#Hoover1 and Nose/Hoover pressure barostat
"(Hoover2)"_#Hoover2, implemented as described in
"(Melchionna)"_#Melchionna. P is pressure; T is temperature. This
creates a system trajectory consistent with the isothermal-isobaric
ensemble.
The desired temperature at each timestep is a ramped value during the
run from {Tstart} to {Tstop}. The {Tdamp} parameter is specified in
@ -189,3 +191,15 @@ the Nose/Hoover formulation.
[Default:]
The keyword defaults are drag = 0.0 and dilate = all.
:line
:link(Hoover1)
[(Hoover1)] Hoover, Phys Rev A, 31, 1695 (1985).
:link(Hoover2)
[(Hoover2)] Hoover, Phys Rev A, 34, 2499 (1986).
:link(Melchionna)
[(Melchionna)] Melchionna, Ciccotti, Holian, Molecular Physics, 78,
533-44 (1993).

View File

@ -40,8 +40,8 @@ fix 1 all nvt 300.0 300.0 100.0 drag 0.2
</P>
<P>Perform constant NVT integration to update positions and velocities
each timestep for atoms in the group using a Nose/Hoover temperature
thermostat. V is volume; T is temperature. This creates a system
trajectory consistent with the canonical ensemble.
thermostat <A HREF = "#Hoover">(Hoover)</A>. V is volume; T is temperature. This
creates a system trajectory consistent with the canonical ensemble.
</P>
<P>The desired temperature at each timestep is a ramped value during the
run from <I>Tstart</I> to <I>Tstop</I>. The <I>Tdamp</I> parameter is specified in
@ -125,4 +125,10 @@ temp/rescale</A>, <A HREF = "fix_langevin.html">fix langevin</A>,
</P>
<P>The keyword defaults are drag = 0.0.
</P>
<HR>
<A NAME = "Hoover"></A>
<P><B>(Hoover)</B> Hoover, Phys Rev A, 31, 1695 (1985).
</P>
</HTML>

View File

@ -31,8 +31,8 @@ fix 1 all nvt 300.0 300.0 100.0 drag 0.2 :pre
Perform constant NVT integration to update positions and velocities
each timestep for atoms in the group using a Nose/Hoover temperature
thermostat. V is volume; T is temperature. This creates a system
trajectory consistent with the canonical ensemble.
thermostat "(Hoover)"_#Hoover. V is volume; T is temperature. This
creates a system trajectory consistent with the canonical ensemble.
The desired temperature at each timestep is a ramped value during the
run from {Tstart} to {Tstop}. The {Tdamp} parameter is specified in
@ -115,3 +115,8 @@ temp/rescale"_fix_temp_rescale.html, "fix langevin"_fix_langevin.html,
[Default:]
The keyword defaults are drag = 0.0.
:line
:link(Hoover)
[(Hoover)] Hoover, Phys Rev A, 31, 1695 (1985).