This is a typical MD problem in SIESTA. It has been discussed several time here. Kindly go through the old threads, you will find an answer. Best of Luck.
<https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=icon> Virus-free. www.avast.com <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail&utm_term=link> <#DDB4FAA8-2DD7-40BB-A1B8-4E2AA1F9FDF2> On Wed, Jun 1, 2016 at 6:25 PM, ZARA NBSH <[email protected]> wrote: > Dear all, > I am new in siesta and would like to perform molecular dynamics > calculation on graphene sheet with periodic boundary conditions and the > total number of C atoms 200. > > I set the temperature to 300K, but in the output the temperature > fluctuations are very large between 230 to 360 K. > I copy the input file here. > Would any one help me what is wrong in my calculations? > > > > # fdf file > > SystemName graphene > SystemLabel c > > NumberOfAtoms 200 > NumberOfSpecies 1 > > %block ChemicalSpeciesLabel > 1 6 C > %endblock ChemicalSpeciesLabel > > XC.functional GGA > XC.authors PBE > > > LatticeConstant 2.471763457 Ang > > %block LatticeParameters > 10 8.66025404 8 90. 90. 90. > %endblock LatticeParameters > > AtomicCoordinatesFormat Ang > AtomicCoordinatesAndAtomicSpecies < xyz > > > %block kgrid_Monkhorst_Pack > 1 0 0 0.0 > 0 1 0 0.0 > 0 0 1 0.0 > %endblock kgrid_Monkhorst_Pack > > MeshCutoff 300.0 Ry > > # SCF options > MaxSCFIterations 100 # Maximum number of SCF iter > DM.NumberPulay 3 # One Pulay every 3 iter > DM.MixingWeight 0.25 # New DM amount for next SCF cycle > DM.Tolerance 5.d-4 # Tolerance in maximum difference > > SolutionMethod diagon # OrderN or Diagon > ElectronicTemperature 25 meV # Temp. for Fermi smearing > > > # structural infomation > AtomCoorFormatOut Ang > WriteCoorXmol T > WriteMDXmol T > WriteForces T > > # options for MD > MD.MaxForceTol 0.01 eV/Ang > MD.TypeOfRun Nose > MD.VariableCell T > MD.NumCGSteps 400 > MD.Broyden.History.Steps 6 > MD.Broyden.Initial.Inverse.Jacobian 1.0 > > > MD.InitialTimeStep 1 > MD.FinalTimeStep 2000 > MD.LengthTimeStep 1 fs > MD.InitialTemperature 300 K > MD.TargetTemperature 300 K > MD.AnnealOption TemperatureAndPressure > MD.TauRelax 100.0 fs > >
