[Pw_forum] Temperature continuously going down in cp.x run

[vega lew]

dear all,

I want to calculate certain heterogeneous reaction on a solid surface.
First input the initial structure from previous pw.x relaxations.
Second I fixed ions and let electron damping calculation run;
Then un-fixed the ions and let both electron  and ions damping calculations
run.
Third I gave a random motion to the atoms in the system with amprp(1)~(3) =
0.01
and then repeated second step to bring the system to the ground state.
Fourth I added temperature (300K) to the system, using verlet schedule.

But the temperature continuously going down, from 1000K to 150K during the
fisrt 3000 steps.
I think there might be something wrong with my cp.x calcuation.
Do you think the amprp(1)~(3) = 0.01 of random motion is too small?

Here is the input of my dynamics process,
 &CONTROL

                       title = 'CP' ,

                 calculation = 'cp'
,
                restart_mode = 'restart'
,
                      outdir = '/disk5/nanjing/vega/cp/300/' ,
                      wfcdir = '/tmp/'
,
                  pseudo_dir =
'/home/software/nanjing/vega/espresso-4.0.1/pseudo/' ,
                      prefix = 'cp_molecular' ,
                       nstep = 99999 ,
                          dt = 10,
                      iprint = 5,
                       isave =
150,
 /

 &SYSTEM

                       ibrav =
8,
                   celldm(1) =24.8624,
                   celldm(2) = 0.8520,
                   celldm(3) = 1.6964,
                         nat =
147,
                        ntyp = 3,
                        nr1b = 20,
                        nr2b = 20,
                        nr3b = 20,
                        nbnd =
630,
                   ecutwfc   =   30,
                   ecutrho   =  300,
 /


 &ELECTRONS
           electron_dynamics = 'verlet',
 /

 &IONS

                ion_dynamics = 'verlet'
             ion_temperature = 'nose',
                       tempw = 300,
 /
..................
..................

best wishes,

vega

-- 
==================================================================================
Vega Lew ( weijia liu)
Graduate student
State Key Laboratory of Materials-oriented Chemical Engineering
College of Chemistry and Chemical Engineering
Nanjing University of Technology, 210009, Nanjing, Jiangsu, China
******************************************************************************************************************
Email: vegalew at gmail.com
Office: Room A705, Technical Innovation Building, Xinmofan Road 5#, Nanjing,
Jiangsu, China
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