[CPMD-list] question on the QUENCH[IONS,ELECTRONS,CELL,BO] keyword

[huawj]

Dear All£¬

I tried the keyword 	
         QUENCH BO ELECTRON   
for a (31H2O +HCl) system at 300K(which started from a equilibrated configuration using classical MD and relaxed for 1 ps using CPMD),
but get confused about the following questions:  

(1)  From the cpmd-manual, I can read the illustrations for this keyword:
"The velocities of the ions, wavefunctions or the cell are set to _zero_ at the beginning of the run.
With the option BO the wavefunctions are converged at the beginning of the MD run.  "

But why here the resulting EKINC of the first step is not _zero_ , but a positive value instead ?

       NFI    EKINC   TEMPP           EKS      ECLASSIC          EHAM         DIS    TCPU
         1  0.00040   302.0    -490.88033    -490.74549    -490.74509   0.486E-04    8.31
         2  0.00362   285.0    -490.87575    -490.74849    -490.74487   0.189E-03    8.34
         3  0.01012   300.0    -490.87335    -490.73940    -490.72928   0.412E-03    8.32
         4  0.01866   280.9    -490.87342    -490.74801    -490.72935   0.727E-03    8.33
         5  0.02698   300.0    -490.87535    -490.74140    -490.71442   0.112E-02    8.34
           ......
        48  0.02502   315.3    -490.88021    -490.73946    -490.71443   0.959E-01    9.44
        49  0.02513   316.6    -490.88090    -490.73955    -490.71443   0.995E-01    9.39
        50  0.02529   317.8    -490.88163    -490.73972    -490.71443   0.103E+00    9.45



(2) Why the "quench to the BO surface" step should not take more than 50 steps ?

(3) In the case the running takes more than 50 steps, I adjusted the convergence parameter (CONVERGENCE ORBITALS 2.0E-5), but nothing changed in the output file. Even no statement about the convergence creteria can be found in the output file. Why can this happen?

(4) Suppose I have converged the wavefunctions with the creteria  2.0E-5 in less than 50 steps, is there anything else should I do before
I start a simulation of trajectory using a Nose-Hoover chain thermostat? Should I reoptimize the wavefunction to get a much higher convergence creteria, e.g. 1.0E-6 ?  

Thank you very much. 

==input file for quenching the electrons to the BO surface======

&CPMD
MOLECULAR DYNAMICS CP
RESTART WAVEFUNCTION  COORDINATES VELOCITIES
QUENCH BO ELECTRONS
TRAJECTORY XYZ
TEMPERATURE
 300.0
TEMPCONTROL IONS
 300.0 30.0
TIMESTEP
7.0
MAXSTEP
50
EMASS
1000.0
MEMORY BIG
&END







¡¡¡¡
Best regards, 				

Weijie Hua
Institute of Theoretical and Computational Chemistry,
Key Laboratory of Mesoscopic Chemistry,
School of Chemistry and Chemical Engineering,
Nanjing University,Nanjing 210093,
P.R.China
Email:huawj at itcc.nju.edu.cn
2006-10-04