[CPMD-list] help on the kohn-sham energies!
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shyma at imr.ac.cn
Tue Dec 13 09:37:30 CET 2005
Dear axel and cpmd-users:
Thanks for your kindly reply!
Today I have other questions need your help!
Firstly, I have optimized the wavefunction of the 5 atoms clusters and recalculated the kohn-sham energyes of it, but I find the final total energys is different,but I don't know what's the reason cause the difference. The following are the input and out files in different calculation respectively:
input file for the wavefunction optimization:
*********************************************
&CPMD
OPTIMIZE WAVEFUNCTION
CONVERGENCE ORBITALS
1.0D-5
FREE ENERGY FUNCTIONAL
LANCZOS DIAGONALISATION
LANCZOS PARAMETAERS N=5
1 6 20 1.0D-9
0.05 1.0D-10
0.01 1.0D-12
0.0025 1.0D-14
0.001 1.0D-16
ANDERSON MIXING
0.2
BROYDEN MIXING
BROYMIX=0.15
TEMPERATURE ELCECTRON
1000
CENTER MOLECULE ON
MAXSTEP
1000
STRUCTURE BONDS ANGLES
MIRROR
&END
&SYSTEM
SYMMETRY
0
POISSON SOLVER TUCKERMAN
ANGSTROM
CELL
18.0 1.0 1.0 0.0 0.0 0.0
STATES
12
CUTOFF
60
&END
&ATOMS
*Al_SGS_LDA.psp KLEINMAN-BYLANDER
LMAX=D
5
9.627618698838 10.483425410635 8.869432662311
10.799305233317 8.197179013185 8.528215175287
8.342182486388 8.284268303325 7.708984912400
9.030290923963 8.232406355001 10.421762121950
7.200662913258 9.802781813240 9.471731059454
&END
&DFT
FUNCTIONAL LDA
&END
input for the khon-sham energies:
********************************
&CPMD
KOHN-SHAM ENERGIES
8
RESTART WAVEFUNCTION COORDINATES
FREE ENERGY FUNCTIONAL
LANCZOS DIAGONALIZATION
RHOOUT
ELECTROSTATIC POTENTIAL
ELF
CONVERGENCE ORBITALS
1.0D-5
CENTER MOLECULE ON
TEMPERATURE ELECTRON
1000
MIRROR
&END
&SYSTEM
SYMMETRY
0
POISSON SOLVER TUCKERMAN
ANGSTROM
CELL
18.0 1.0 1.0 0.0 0.0 0.0
CUTOFF
60
&END
&DFT
FUNCTIONAL LDA
&END
&ATOMS
*Al_SGS_LDA.psp KLEINMAN-BYLANDER
LMAX=D
5
9.627618698838 10.483425410635 8.869432662311
10.799305233317 8.197179013185 8.528215175287
8.342182486388 8.284268303325 7.708984912400
9.030290923963 8.232406355001 10.421762121950
7.200662913258 9.802781813240 9.471731059454
&END
the final results for the wavefunction optimization:
****************************************************************
EIGENVALUES(EV) AND OCCUPATION:
1 -12.1696122 2.000 2 -8.8559503 2.000
3 -7.9476996 2.000 4 -7.9473935 2.000
5 -5.7240799 2.000 6 -4.7316987 1.988
7 -4.3800213 1.465 8 -4.3798610 1.464
9 -3.9610614 0.041 10 -3.9609183NC 0.041
11 -3.4441107NC 0.000 12 -1.4512370NC 0.000
CHEMICAL POTENTIAL = -4.2932170551 EV
****************************************************************
ELECTRONIC GRADIENT:
MAX. COMPONENT = 9.04632E-06 NORM = 2.01259E-06
TOTAL INTEGRATED ELECTRONIC DENSITY
IN G-SPACE = 15.000000
IN R-SPACE = 15.000000
(F+E2+X-V+O) TOTAL ENERGY = -10.13365518 A.U.
(F) ELECTRONIC FREE ENERGY = -3.97233193 A.U.
(E2=I-H-S+R) ELECTROSTATIC ENERGY = -7.20586331 A.U.
(S) ESELF = 14.96033552 A.U.
(R) ESR = 0.00054749 A.U.
(X) EXCHANGE-CORRELATION ENERGY = -3.45753883 A.U.
(V) EXCHANGE-CORRELATION POTEN. = -4.50207656 A.U.
(O) BOGOLIUBOV CORRECTION ENERGY = 0.00000233 A.U.
*****************************************************************
and final results for the kohn-sham energies:
****************************************************************
EIGENVALUES(EV) AND OCCUPATION:
1 -12.1738143 2.000 2 -8.8233432 2.000
3 -8.2125551 2.000 4 -7.7129732 2.000
5 -5.6818952 2.000 6 -4.8253746 1.999
7 -4.5739314 1.979 8 -4.1403639 0.761
9 -3.9798900 0.174 10 -3.9165498 0.087
11 -3.3955067 0.000 12 -1.5688794 0.000
13 -1.3219857 0.000 14 -0.8650114NC 0.000
15 -0.7020890NC 0.000 16 -0.3384448NC 0.000
CHEMICAL POTENTIAL = -4.1824507416 EV
****************************************************************
ELECTRONIC GRADIENT:
MAX. COMPONENT = 9.86609E-03 NORM = 2.54834E+00
TOTAL INTEGRATED ELECTRONIC DENSITY
IN G-SPACE = 15.000000
IN R-SPACE = 15.000000
(F+E2+X-V+O) TOTAL ENERGY = -10.15535475 A.U.
(F) ELECTRONIC FREE ENERGY = -3.97978925 A.U.
(E2=I-H-S+R) ELECTROSTATIC ENERGY = -7.22134101 A.U.
(S) ESELF = 14.96033552 A.U.
(R) ESR = 0.00054749 A.U.
(X) EXCHANGE-CORRELATION ENERGY = -3.46149018 A.U.
(V) EXCHANGE-CORRELATION POTEN. = -4.50726336 A.U.
(O) BOGOLIUBOV CORRECTION ENERGY = 0.00000233 A.U.
****************************************************************
You can see the difference what I mean from the above files. The final results "TOTAL ENERGY" "EIGENVALUES(EV) AND OCCUPATION" and "CHEMICAL POTENTIAL(is it the Fermi energy?)" are all not the same for the wavefunction calculation and kohn-sham energies calculation. So what cause the difference and which results are more correct? Are there some faults in my 2 input files?
Secondly, what's the meaning of "NC" in the "EIGENVALUES(EV) AND OCCUPATION" results if the results show the occupation stats? Does it mean "not converged"? Is there any difference between the "13 -1.3219857 0.000 " and "14 -0.8650114NC 0.000"? The occupation of all them are 0 and "14" indentfied NC and "13" is not.
Any comments and advices are appreciated!
Thanks in advance!
Best regards!
shyma
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